21602688416 has 48 divisors (see below), whose sum is σ = 43117215624. Its totient is φ = 10653057024.

The previous prime is 21602688353. The next prime is 21602688431. The reversal of 21602688416 is 61488620612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 21579610000 + 23078416 = 146900^2 + 4804^2 .

It is a super-2 number, since 2×21602688416² (a number of 21 digits) contains 22 as substring.

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, 897596 + ... + 921348.

Almost surely, 2^21602688416 is an apocalyptic number.

It is an amenable number.

21602688416 is a deficient number, since it is larger than the sum of its proper divisors (21514527208).

21602688416 is a wasteful number, since it uses less digits than its factorization.

21602688416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24153 (or 24145 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 44.

The spelling of 21602688416 in words is "twenty-one billion, six hundred two million, six hundred eighty-eight thousand, four hundred sixteen".