21689631076 has 9 divisors (see below), whose sum is σ = 37957369849. Its totient is φ = 10844668264.

The previous prime is 21689631053. The next prime is 21689631109. The reversal of 21689631076 is 67013698612.

The square root of 21689631076 is 147274.

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

It can be written as a sum of positive squares in only one way, i.e., 21459320100 + 230310976 = 146490^2 + 15176^2 .

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, 257730 + ... + 331366.

Almost surely, 2^21689631076 is an apocalyptic number.

21689631076 is the 147274-th square number.

It is an amenable number.

21689631076 is a deficient number, since it is larger than the sum of its proper divisors (16267738773).

21689631076 is an frugal number, since it uses more digits than its factorization.

21689631076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147278 (or 73639 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 49.

Multiplying 21689631076 by its sum of digits (49), we get a square (1062791922724 = 1030918²).

The spelling of 21689631076 in words is "twenty-one billion, six hundred eighty-nine million, six hundred thirty-one thousand, seventy-six".