21189992 has 16 divisors (see below), whose sum is σ = 41459040. Its totient is φ = 10134256.

The previous prime is 21189977. The next prime is 21190003. The reversal of 21189992 is 29998112.

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 3 ways as a sum of consecutive naturals, for example, 57398 + ... + 57765.

It is an arithmetic number, because the mean of its divisors is an integer number (2591190).

Almost surely, 2^21189992 is an apocalyptic number.

It is an amenable number.

21189992 is a deficient number, since it is larger than the sum of its proper divisors (20269048).

21189992 is a wasteful number, since it uses less digits than its factorization.

21189992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115192 (or 115188 counting only the distinct ones).

The product of its digits is 23328, while the sum is 41.

The square root of 21189992 is about 4603.2588456440. The cubic root of 21189992 is about 276.7219424725.

The spelling of 21189992 in words is "twenty-one million, one hundred eighty-nine thousand, nine hundred ninety-two".