21444475756 has 24 divisors (see below), whose sum is σ = 41233993920. Its totient is φ = 9677360400.

The previous prime is 21444475751. The next prime is 21444475757. The reversal of 21444475756 is 65757444412.

It is not an unprimeable number, because it can be changed into a prime (21444475751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1747030 + ... + 1759261.

It is an arithmetic number, because the mean of its divisors is an integer number (1718083080).

Almost surely, 2^21444475756 is an apocalyptic number.

It is an amenable number.

21444475756 is a deficient number, since it is larger than the sum of its proper divisors (19789518164).

21444475756 is a wasteful number, since it uses less digits than its factorization.

21444475756 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3506445 (or 3506443 counting only the distinct ones).

The product of its digits is 3763200, while the sum is 49.

The spelling of 21444475756 in words is "twenty-one billion, four hundred forty-four million, four hundred seventy-five thousand, seven hundred fifty-six".