21889992 has 16 divisors (see below), whose sum is σ = 54725040. Its totient is φ = 7296656.

The previous prime is 21889991. The next prime is 21889993. The reversal of 21889992 is 29998812.

It is an interprime number because it is at equal distance from previous prime (21889991) and next prime (21889993).

It is not an unprimeable number, because it can be changed into a prime (21889991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 456018 + ... + 456065.

It is an arithmetic number, because the mean of its divisors is an integer number (3420315).

Almost surely, 2^21889992 is an apocalyptic number.

It is an amenable number.

21889992 is an abundant number, since it is smaller than the sum of its proper divisors (32835048).

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

21889992 is a wasteful number, since it uses less digits than its factorization.

21889992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 912092 (or 912088 counting only the distinct ones).

The product of its digits is 186624, while the sum is 48.

The square root of 21889992 is about 4678.6741711729. The cubic root of 21889992 is about 279.7361119191.

The spelling of 21889992 in words is "twenty-one million, eight hundred eighty-nine thousand, nine hundred ninety-two".