21706640896 has 40 divisors (see below), whose sum is σ = 45653584680. Its totient is φ = 10282088448.

The previous prime is 21706640887. The next prime is 21706640909. The reversal of 21706640896 is 69804660712.

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, 1105951 + ... + 1125406.

It is an arithmetic number, because the mean of its divisors is an integer number (1141339617).

Almost surely, 2^21706640896 is an apocalyptic number.

It is an amenable number.

21706640896 is an abundant number, since it is smaller than the sum of its proper divisors (23946943784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21706640896 is an equidigital number, since it uses as much as digits as its factorization.

21706640896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2231394 (or 2231378 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 49.

The spelling of 21706640896 in words is "twenty-one billion, seven hundred six million, six hundred forty thousand, eight hundred ninety-six".