22091988 has 24 divisors (see below), whose sum is σ = 51768640. Its totient is φ = 7332480.

The previous prime is 22091947. The next prime is 22091999. The reversal of 22091988 is 88919022.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

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, 928 + ... + 6711.

Almost surely, 2^22091988 is an apocalyptic number.

It is an amenable number.

22091988 is an abundant number, since it is smaller than the sum of its proper divisors (29676652).

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

22091988 is a wasteful number, since it uses less digits than its factorization.

22091988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7887 (or 7885 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 39.

The square root of 22091988 is about 4700.2114846036. The cubic root of 22091988 is about 280.5939263679.

The spelling of 22091988 in words is "twenty-two million, ninety-one thousand, nine hundred eighty-eight".