56672021891 has 16 divisors (see below), whose sum is σ = 58383840384. Its totient is φ = 54987729984.

The previous prime is 56672021881. The next prime is 56672021893. The reversal of 56672021891 is 19812027665.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56672021891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56672021893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3841856 + ... + 3856578.

It is an arithmetic number, because the mean of its divisors is an integer number (3648990024).

Almost surely, 2^56672021891 is an apocalyptic number.

56672021891 is a deficient number, since it is larger than the sum of its proper divisors (1711818493).

56672021891 is a wasteful number, since it uses less digits than its factorization.

56672021891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15650.

The product of its (nonzero) digits is 362880, while the sum is 47.

The spelling of 56672021891 in words is "fifty-six billion, six hundred seventy-two million, twenty-one thousand, eight hundred ninety-one".