21980888 has 8 divisors (see below), whose sum is σ = 41214180. Its totient is φ = 10990440.

The previous prime is 21980857. The next prime is 21980897. The reversal of 21980888 is 88808912.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1373798 + ... + 1373813.

Almost surely, 2^21980888 is an apocalyptic number.

It is an amenable number.

21980888 is a deficient number, since it is larger than the sum of its proper divisors (19233292).

21980888 is a wasteful number, since it uses less digits than its factorization.

21980888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2747617 (or 2747613 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 44.

The square root of 21980888 is about 4688.3779711111. The cubic root of 21980888 is about 280.1227692917.

The spelling of 21980888 in words is "twenty-one million, nine hundred eighty thousand, eight hundred eighty-eight".