20993888 has 24 divisors (see below), whose sum is σ = 41485752. Its totient is φ = 10457856.

The previous prime is 20993873. The next prime is 20993897. The reversal of 20993888 is 88839902.

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, 8756 + ... + 10892.

It is an arithmetic number, because the mean of its divisors is an integer number (1728573).

Almost surely, 2^20993888 is an apocalyptic number.

It is an amenable number.

20993888 is a deficient number, since it is larger than the sum of its proper divisors (20491864).

20993888 is a wasteful number, since it uses less digits than its factorization.

20993888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2454 (or 2446 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 47.

The square root of 20993888 is about 4581.9087725532. The cubic root of 20993888 is about 275.8656490972.

The spelling of 20993888 in words is "twenty million, nine hundred ninety-three thousand, eight hundred eighty-eight".