21956800 has 42 divisors (see below), whose sum is σ = 54031388. Its totient is φ = 8782080.

The previous prime is 21956777. The next prime is 21956801. The reversal of 21956800 is 865912.

It is not an unprimeable number, because it can be changed into a prime (21956801) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5262 + ... + 8461.

Almost surely, 2^21956800 is an apocalyptic number.

21956800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21956800 is an abundant number, since it is smaller than the sum of its proper divisors (32074588).

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

21956800 is a wasteful number, since it uses less digits than its factorization.

21956800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13745 (or 13730 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 21956800 is about 4685.8083614250. The cubic root of 21956800 is about 280.0204066760.

The spelling of 21956800 in words is "twenty-one million, nine hundred fifty-six thousand, eight hundred".