12911257 has 4 divisors (see below), whose sum is σ = 13472640. Its totient is φ = 12349876.

The previous prime is 12911251. The next prime is 12911263. The reversal of 12911257 is 75211921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (12911251) and next prime (12911263).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12911257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12911251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 280657 + ... + 280702.

It is an arithmetic number, because the mean of its divisors is an integer number (3368160).

Almost surely, 2^12911257 is an apocalyptic number.

It is an amenable number.

12911257 is a deficient number, since it is larger than the sum of its proper divisors (561383).

12911257 is an equidigital number, since it uses as much as digits as its factorization.

12911257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 561382.

The product of its digits is 1260, while the sum is 28.

The square root of 12911257 is about 3593.2237614710. The cubic root of 12911257 is about 234.5972095127.

The spelling of 12911257 in words is "twelve million, nine hundred eleven thousand, two hundred fifty-seven".