21628996624 has 15 divisors (see below), whose sum is σ = 41907320767. Its totient is φ = 10814204176.

The previous prime is 21628996583. The next prime is 21628996633. The reversal of 21628996624 is 42669982612.

The square root of 21628996624 is 147068.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×21628996624² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 569889 + ... + 606655.

Almost surely, 2^21628996624 is an apocalyptic number.

21628996624 is the 147068-th square number.

It is an amenable number.

21628996624 is a deficient number, since it is larger than the sum of its proper divisors (20278324143).

21628996624 is an frugal number, since it uses more digits than its factorization.

21628996624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73542 (or 36769 counting only the distinct ones).

The product of its digits is 4478976, while the sum is 55.

The spelling of 21628996624 in words is "twenty-one billion, six hundred twenty-eight million, nine hundred ninety-six thousand, six hundred twenty-four".