21331838356 has 12 divisors (see below), whose sum is σ = 37421993140. Its totient is φ = 10639840320.

The previous prime is 21331838329. The next prime is 21331838371. The reversal of 21331838356 is 65383813312.

It can be written as a sum of positive squares in 2 ways, for example, as 12586596100 + 8745242256 = 112190^2 + 93516^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6517875 + ... + 6521146.

Almost surely, 2^21331838356 is an apocalyptic number.

It is an amenable number.

21331838356 is a deficient number, since it is larger than the sum of its proper divisors (16090154784).

21331838356 is a wasteful number, since it uses less digits than its factorization.

21331838356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13039434 (or 13039432 counting only the distinct ones).

The product of its digits is 311040, while the sum is 43.

The spelling of 21331838356 in words is "twenty-one billion, three hundred thirty-one million, eight hundred thirty-eight thousand, three hundred fifty-six".