256621721431272 has 64 divisors (see below), whose sum is σ = 641794201305600. Its totient is φ = 85508593410240.

The previous prime is 256621721431139. The next prime is 256621721431349. The reversal of 256621721431272 is 272134127126652.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 709214703 + ... + 709576449.

It is an arithmetic number, because the mean of its divisors is an integer number (10028034395400).

Almost surely, 2^{256621721431272} is an apocalyptic number.

It is an amenable number.

256621721431272 is an abundant number, since it is smaller than the sum of its proper divisors (385172479874328).

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

256621721431272 is a wasteful number, since it uses less digits than its factorization.

256621721431272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 372726 (or 372722 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 51.

The spelling of 256621721431272 in words is "two hundred fifty-six trillion, six hundred twenty-one billion, seven hundred twenty-one million, four hundred thirty-one thousand, two hundred seventy-two".