21926920 has 32 divisors (see below), whose sum is σ = 50929920. Its totient is φ = 8487360.

The previous prime is 21926917. The next prime is 21926939. The reversal of 21926920 is 2962912.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7602 + ... + 10081.

It is an arithmetic number, because the mean of its divisors is an integer number (1591560).

Almost surely, 2^21926920 is an apocalyptic number.

21926920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21926920 is an abundant number, since it is smaller than the sum of its proper divisors (29003000).

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

21926920 is a wasteful number, since it uses less digits than its factorization.

21926920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17725 (or 17721 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 21926920 is about 4682.6189253451. The cubic root of 21926920 is about 279.8933267121.

The spelling of 21926920 in words is "twenty-one million, nine hundred twenty-six thousand, nine hundred twenty".