12640374257 has 16 divisors (see below), whose sum is σ = 14525955072. Its totient is φ = 10774829520.

The previous prime is 12640374239. The next prime is 12640374277. The reversal of 12640374257 is 75247304621.

It is not a de Polignac number, because 12640374257 - 2¹² = 12640370161 is a prime.

It is a super-2 number, since 2×12640374257² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12640374277) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2542388 + ... + 2547354.

It is an arithmetic number, because the mean of its divisors is an integer number (907872192).

Almost surely, 2^12640374257 is an apocalyptic number.

It is an amenable number.

12640374257 is a deficient number, since it is larger than the sum of its proper divisors (1885580815).

12640374257 is a wasteful number, since it uses less digits than its factorization.

12640374257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6908.

The product of its (nonzero) digits is 282240, while the sum is 41.

Adding to 12640374257 its reverse (75247304621), we get a palindrome (87887678878).

The spelling of 12640374257 in words is "twelve billion, six hundred forty million, three hundred seventy-four thousand, two hundred fifty-seven".