21138465704 has 16 divisors (see below), whose sum is σ = 39669746100. Its totient is φ = 10559866752.

The previous prime is 21138465641. The next prime is 21138465731. The reversal of 21138465704 is 40756483112.

It can be written as a sum of positive squares in 2 ways, for example, as 21120808900 + 17656804 = 145330^2 + 4202^2 .

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, 1161167 + ... + 1179230.

Almost surely, 2^21138465704 is an apocalyptic number.

It is an amenable number.

21138465704 is a deficient number, since it is larger than the sum of its proper divisors (18531280396).

21138465704 is a wasteful number, since it uses less digits than its factorization.

21138465704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2341532 (or 2341528 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 41.

The spelling of 21138465704 in words is "twenty-one billion, one hundred thirty-eight million, four hundred sixty-five thousand, seven hundred four".