21002664664 has 32 divisors (see below), whose sum is σ = 40828860000. Its totient is φ = 10116585472.

The previous prime is 21002664649. The next prime is 21002664679. The reversal of 21002664664 is 46646620012.

It is an interprime number because it is at equal distance from previous prime (21002664649) and next prime (21002664679).

It is a super-2 number, since 2×21002664664² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 3357 + ... + 204979.

It is an arithmetic number, because the mean of its divisors is an integer number (1275901875).

Almost surely, 2^21002664664 is an apocalyptic number.

It is an amenable number.

21002664664 is a deficient number, since it is larger than the sum of its proper divisors (19826195336).

21002664664 is a wasteful number, since it uses less digits than its factorization.

21002664664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202107 (or 202103 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 37.

The spelling of 21002664664 in words is "twenty-one billion, two million, six hundred sixty-four thousand, six hundred sixty-four".