21922870 has 32 divisors (see below), whose sum is σ = 40870368. Its totient is φ = 8460288.

The previous prime is 21922853. The next prime is 21922889. The reversal of 21922870 is 7822912.

It is a super-2 number, since 2×21922870² = 961224458073800, which contains 22 as substring.

It is a congruent number.

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, 71257 + ... + 71563.

It is an arithmetic number, because the mean of its divisors is an integer number (1277199).

Almost surely, 2^21922870 is an apocalyptic number.

21922870 is a deficient number, since it is larger than the sum of its proper divisors (18947498).

21922870 is a wasteful number, since it uses less digits than its factorization.

21922870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 21922870 is about 4682.1864550656. The cubic root of 21922870 is about 279.8760931354.

The spelling of 21922870 in words is "twenty-one million, nine hundred twenty-two thousand, eight hundred seventy".