12656542440 has 64 divisors (see below), whose sum is σ = 38211528960. Its totient is φ = 3353575680.

The previous prime is 12656542433. The next prime is 12656542463. The reversal of 12656542440 is 4424565621.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 317056 + ... + 354735.

It is an arithmetic number, because the mean of its divisors is an integer number (597055140).

Almost surely, 2^12656542440 is an apocalyptic number.

12656542440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12656542440 is an abundant number, since it is smaller than the sum of its proper divisors (25554986520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12656542440 is a wasteful number, since it uses less digits than its factorization.

12656542440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671962 (or 671958 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 39.

The spelling of 12656542440 in words is "twelve billion, six hundred fifty-six million, five hundred forty-two thousand, four hundred forty".