Compare 13 vs 31

Unique factors11
Total factors11
Prime factorization131311
Prime factorization1331
Divisors count22
Divisors1, 131, 31
Number of properties3218
Centered decagonal primes 2nd
Centered square primes2nd 
Centered triangular primes 2nd
Chen primes6th11th
Class 1+ primes 8th
Cousin primes (1st member)3rd 
Cuban primes 21st 
Euclid primes 4th
Fibonacci primes4th 
Happy primes2nd5th
Harmonic primes2nd 
Left-truncatable primes5th 
Lucky primes3rd4th
Mersenne primes 3rd
Multiplicative primes5th7th
Pierpont primes5th 
Pierpont primes of the 2nd kind 8th
Prime quadruplets (2nd member)2nd 
Prime quadruplets (4th member)1st 
Prime quintuplet 1s (3rd member)1st 
Prime quintuplet 2s (2nd member)2nd 
Prime quintuplet 2s (4th member)1st 
Prime sextuplets (3rd member)1st 
Prime triplets (1st member)4th 
Prime triplets (2nd member)3rd 
Prime triplets (3rd member)2nd 
Proth primes3rd 
Pythagorean primes2nd 
Right-truncatable primes 7th
Sexy primes (1st member)4th7th
Sexy primes (2nd member)2nd 
Sexy prime triplets (1st member) 5th
Sexy prime triplets (2nd member)2nd 
Solinas primes5th10th
Super primes 5th
Thabit primes of the 2nd kind2nd 
Twin primes (2nd member)3rd5th
Ulam primes4th 
Wilson primes2nd 
Roman numberalsXIIIXXXI
Base 211012111112
Base 3111310113
Base 43141334
Base 52351115
Base 6216516
Base 7167437
Base 8158378
Base 9149349
Base 1013103110
Base 1112112911
Base 1211122712
Base 1310132513
Base 14d142314
Base 15d152115
Base 16d161f16
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