21990314646 has 48 divisors (see below), whose sum is σ = 49450250304. Its totient is φ = 7324183944.

The previous prime is 21990314629. The next prime is 21990314653. The reversal of 21990314646 is 64641309912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 605905 + ... + 641171.

It is an arithmetic number, because the mean of its divisors is an integer number (1030213548).

Almost surely, 2^21990314646 is an apocalyptic number.

21990314646 is an abundant number, since it is smaller than the sum of its proper divisors (27459935658).

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

21990314646 is a wasteful number, since it uses less digits than its factorization.

21990314646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36567 (or 36555 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The spelling of 21990314646 in words is "twenty-one billion, nine hundred ninety million, three hundred fourteen thousand, six hundred forty-six".