20871868 has 12 divisors (see below), whose sum is σ = 37026640. Its totient is φ = 10292832.

The previous prime is 20871863. The next prime is 20871881. The reversal of 20871868 is 86817802.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20871868.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20871863) 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, 35448 + ... + 36031.

Almost surely, 2^20871868 is an apocalyptic number.

It is an amenable number.

20871868 is a deficient number, since it is larger than the sum of its proper divisors (16154772).

20871868 is a wasteful number, since it uses less digits than its factorization.

20871868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71556 (or 71554 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 40.

The square root of 20871868 is about 4568.5739569367. The cubic root of 20871868 is about 275.3301511370.

The spelling of 20871868 in words is "twenty million, eight hundred seventy-one thousand, eight hundred sixty-eight".