21879992 has 16 divisors (see below), whose sum is σ = 42809040. Its totient is φ = 10464256.

The previous prime is 21879961. The next prime is 21880009. The reversal of 21879992 is 29997812.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59273 + ... + 59640.

It is an arithmetic number, because the mean of its divisors is an integer number (2675565).

Almost surely, 2^21879992 is an apocalyptic number.

It is an amenable number.

21879992 is a deficient number, since it is larger than the sum of its proper divisors (20929048).

21879992 is a wasteful number, since it uses less digits than its factorization.

21879992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118942 (or 118938 counting only the distinct ones).

The product of its digits is 163296, while the sum is 47.

The square root of 21879992 is about 4677.6053702723. The cubic root of 21879992 is about 279.6935081697.

The spelling of 21879992 in words is "twenty-one million, eight hundred seventy-nine thousand, nine hundred ninety-two".