21945256272 has 60 divisors (see below), whose sum is σ = 64648679680. Its totient is φ = 6930080064.

The previous prime is 21945256243. The next prime is 21945256303. The reversal of 21945256272 is 27265254912.

21945256272 is a `hidden beast` number, since 2 + 19 + 4 + 5 + 2 + 5 + 627 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4007728 + ... + 4013199.

Almost surely, 2^21945256272 is an apocalyptic number.

It is an amenable number.

21945256272 is an abundant number, since it is smaller than the sum of its proper divisors (42703423408).

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

21945256272 is a wasteful number, since it uses less digits than its factorization.

21945256272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8020960 (or 8020951 counting only the distinct ones).

The product of its digits is 604800, while the sum is 45.

The spelling of 21945256272 in words is "twenty-one billion, nine hundred forty-five million, two hundred fifty-six thousand, two hundred seventy-two".