21911992 has 16 divisors (see below), whose sum is σ = 42195960. Its totient is φ = 10659744.

The previous prime is 21911987. The next prime is 21912013. The reversal of 21911992 is 29911912.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36718 + ... + 37309.

Almost surely, 2^21911992 is an apocalyptic number.

It is an amenable number.

21911992 is a deficient number, since it is larger than the sum of its proper divisors (20283968).

21911992 is a wasteful number, since it uses less digits than its factorization.

21911992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74070 (or 74066 counting only the distinct ones).

The product of its digits is 2916, while the sum is 34.

The square root of 21911992 is about 4681.0246741499. The cubic root of 21911992 is about 279.8297945162.

The spelling of 21911992 in words is "twenty-one million, nine hundred eleven thousand, nine hundred ninety-two".