12657709 has 4 divisors (see below), whose sum is σ = 12757504. Its totient is φ = 12557916.

The previous prime is 12657691. The next prime is 12657721. The reversal of 12657709 is 90775621.

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 a cyclic number.

It is not a de Polignac number, because 12657709 - 2⁷ = 12657581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12657739) 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, 49707 + ... + 49960.

It is an arithmetic number, because the mean of its divisors is an integer number (3189376).

Almost surely, 2^12657709 is an apocalyptic number.

It is an amenable number.

12657709 is a deficient number, since it is larger than the sum of its proper divisors (99795).

12657709 is an equidigital number, since it uses as much as digits as its factorization.

12657709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99794.

The product of its (nonzero) digits is 26460, while the sum is 37.

The square root of 12657709 is about 3557.7674179182. The cubic root of 12657709 is about 233.0513925698.

It can be divided in two parts, 12657 and 709, that added together give a triangular number (13366 = T₁₆₃).

The spelling of 12657709 in words is "twelve million, six hundred fifty-seven thousand, seven hundred nine".