21200880 has 40 divisors (see below), whose sum is σ = 65723472. Its totient is φ = 5653504.

The previous prime is 21200867. The next prime is 21200897. The reversal of 21200880 is 8800212.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

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, 43929 + ... + 44408.

Almost surely, 2^21200880 is an apocalyptic number.

21200880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200880 is an abundant number, since it is smaller than the sum of its proper divisors (44522592).

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

21200880 is a wasteful number, since it uses less digits than its factorization.

21200880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88353 (or 88347 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The square root of 21200880 is about 4604.4413341903. The cubic root of 21200880 is about 276.7693301357.

The spelling of 21200880 in words is "twenty-one million, two hundred thousand, eight hundred eighty".