21980924 has 12 divisors (see below), whose sum is σ = 43961904. Its totient is φ = 9420384.

The previous prime is 21980911. The next prime is 21980947. The reversal of 21980924 is 42908912.

21980924 is an admirable number.

It is a super-2 number, since 2×21980924² = 966322039787552, which contains 22 as substring.

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

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, 392489 + ... + 392544.

It is an arithmetic number, because the mean of its divisors is an integer number (3663492).

Almost surely, 2^21980924 is an apocalyptic number.

It is an amenable number.

21980924 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21980924 is a wasteful number, since it uses less digits than its factorization.

21980924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785044 (or 785042 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 21980924 is about 4688.3818103904. The cubic root of 21980924 is about 280.1229222188.

The spelling of 21980924 in words is "twenty-one million, nine hundred eighty thousand, nine hundred twenty-four".