21552679864 has 16 divisors (see below), whose sum is σ = 40560397920. Its totient is φ = 10736573760.

The previous prime is 21552679843. The next prime is 21552679867. The reversal of 21552679864 is 46897625512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21552679867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4968469 + ... + 4972804.

It is an arithmetic number, because the mean of its divisors is an integer number (2535024870).

Almost surely, 2^21552679864 is an apocalyptic number.

It is an amenable number.

21552679864 is a deficient number, since it is larger than the sum of its proper divisors (19007718056).

21552679864 is a wasteful number, since it uses less digits than its factorization.

21552679864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9941550 (or 9941546 counting only the distinct ones).

The product of its digits is 7257600, while the sum is 55.

The spelling of 21552679864 in words is "twenty-one billion, five hundred fifty-two million, six hundred seventy-nine thousand, eight hundred sixty-four".