21862980 has 48 divisors (see below), whose sum is σ = 68019840. Its totient is φ = 5829984.

The previous prime is 21862957. The next prime is 21862999. The reversal of 21862980 is 8926812.

21862980 is a `hidden beast` number, since 21 + 8 + 629 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19704 + ... + 20783.

It is an arithmetic number, because the mean of its divisors is an integer number (1417080).

Almost surely, 2^21862980 is an apocalyptic number.

21862980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21862980 is an abundant number, since it is smaller than the sum of its proper divisors (46156860).

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

21862980 is a wasteful number, since it uses less digits than its factorization.

21862980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40505 (or 40497 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 21862980 is about 4675.7865648466. The cubic root of 21862980 is about 279.6210008356.

The spelling of 21862980 in words is "twenty-one million, eight hundred sixty-two thousand, nine hundred eighty".