21756053732 has 24 divisors (see below), whose sum is σ = 44124958080. Its totient is φ = 9192697920.

The previous prime is 21756053723. The next prime is 21756053741. The reversal of 21756053732 is 23735065712.

It is an interprime number because it is at equal distance from previous prime (21756053723) and next prime (21756053741).

It is a super-2 number, since 2×21756053732² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21756053732.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5469857 + ... + 5473832.

It is an arithmetic number, because the mean of its divisors is an integer number (1838539920).

Almost surely, 2^21756053732 is an apocalyptic number.

It is an amenable number.

21756053732 is an abundant number, since it is smaller than the sum of its proper divisors (22368904348).

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

21756053732 is a wasteful number, since it uses less digits than its factorization.

21756053732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10943771 (or 10943769 counting only the distinct ones).

The product of its (nonzero) digits is 264600, while the sum is 41.

The spelling of 21756053732 in words is "twenty-one billion, seven hundred fifty-six million, fifty-three thousand, seven hundred thirty-two".