21168580 has 24 divisors (see below), whose sum is σ = 44573760. Its totient is φ = 8444640.

The previous prime is 21168577. The next prime is 21168593. The reversal of 21168580 is 8586112.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

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, 7575 + ... + 9985.

It is an arithmetic number, because the mean of its divisors is an integer number (1857240).

Almost surely, 2^21168580 is an apocalyptic number.

21168580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21168580 is an abundant number, since it is smaller than the sum of its proper divisors (23405180).

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

21168580 is a wasteful number, since it uses less digits than its factorization.

21168580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2859 (or 2857 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 21168580 is about 4600.9325141758. The cubic root of 21168580 is about 276.6287040056.

The spelling of 21168580 in words is "twenty-one million, one hundred sixty-eight thousand, five hundred eighty".