21993882 has 16 divisors (see below), whose sum is σ = 44097312. Its totient is φ = 7313040.

The previous prime is 21993871. The next prime is 21993893. The reversal of 21993882 is 28839912.

It is an interprime number because it is at equal distance from previous prime (21993871) and next prime (21993893).

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, 1828 + ... + 6879.

It is an arithmetic number, because the mean of its divisors is an integer number (2756082).

Almost surely, 2^21993882 is an apocalyptic number.

21993882 is an abundant number, since it is smaller than the sum of its proper divisors (22103430).

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

21993882 is a wasteful number, since it uses less digits than its factorization.

21993882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9133.

The product of its digits is 62208, while the sum is 42.

The square root of 21993882 is about 4689.7635334844. The cubic root of 21993882 is about 280.1779566020.

The spelling of 21993882 in words is "twenty-one million, nine hundred ninety-three thousand, eight hundred eighty-two".