56721994920 has 96 divisors (see below), whose sum is σ = 185692239720. Its totient is φ = 15015444480.

The previous prime is 56721994897. The next prime is 56721994921. The reversal of 56721994920 is 2949912765.

56721994920 is a `hidden beast` number, since 5 + 67 + 2 + 1 + 99 + 492 + 0 = 666.

56721994920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 44107560324 + 12614434596 = 210018^2 + 112314^2 .

It is not an unprimeable number, because it can be changed into a prime (56721994921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 525721 + ... + 624360.

Almost surely, 2^56721994920 is an apocalyptic number.

It is an amenable number.

56721994920 is an abundant number, since it is smaller than the sum of its proper divisors (128970244800).

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

56721994920 is a wasteful number, since it uses less digits than its factorization.

56721994920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150235 (or 1150228 counting only the distinct ones).

The product of its (nonzero) digits is 2449440, while the sum is 54.

The spelling of 56721994920 in words is "fifty-six billion, seven hundred twenty-one million, nine hundred ninety-four thousand, nine hundred twenty".