21957766272 has 192 divisors, whose sum is σ = 68158654200. Its totient is φ = 6745079808.

The previous prime is 21957766267. The next prime is 21957766289. The reversal of 21957766272 is 27266775912.

It is a happy number.

21957766272 is a `hidden beast` number, since 2 + 1 + 9 + 5 + 7 + 7 + 6 + 627 + 2 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 20660037696 + 1297728576 = 143736^2 + 36024^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17865754 + ... + 17866982.

Almost surely, 2^21957766272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21957766272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34079327100).

21957766272 is an abundant number, since it is smaller than the sum of its proper divisors (46200887928).

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

21957766272 is a wasteful number, since it uses less digits than its factorization.

21957766272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2455 (or 2440 counting only the distinct ones).

The product of its digits is 4445280, while the sum is 54.

The spelling of 21957766272 in words is "twenty-one billion, nine hundred fifty-seven million, seven hundred sixty-six thousand, two hundred seventy-two".