21366625724 has 12 divisors (see below), whose sum is σ = 37777076064. Its totient is φ = 10573175424.

The previous prime is 21366625691. The next prime is 21366625751. The reversal of 21366625724 is 42752666312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27533924 + ... + 27534699.

It is an arithmetic number, because the mean of its divisors is an integer number (3148089672).

Almost surely, 2^21366625724 is an apocalyptic number.

It is an amenable number.

21366625724 is a deficient number, since it is larger than the sum of its proper divisors (16410450340).

21366625724 is a wasteful number, since it uses less digits than its factorization.

21366625724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55068724 (or 55068722 counting only the distinct ones).

The product of its digits is 725760, while the sum is 44.

The spelling of 21366625724 in words is "twenty-one billion, three hundred sixty-six million, six hundred twenty-five thousand, seven hundred twenty-four".