20805868 has 6 divisors (see below), whose sum is σ = 36410276. Its totient is φ = 10402932.

The previous prime is 20805853. The next prime is 20805871. The reversal of 20805868 is 86850802.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2600730 + ... + 2600737.

Almost surely, 2^20805868 is an apocalyptic number.

It is an amenable number.

20805868 is a deficient number, since it is larger than the sum of its proper divisors (15604408).

20805868 is a wasteful number, since it uses less digits than its factorization.

20805868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5201471 (or 5201469 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 37.

The square root of 20805868 is about 4561.3449770874. The cubic root of 20805868 is about 275.0396328554.

The spelling of 20805868 in words is "twenty million, eight hundred five thousand, eight hundred sixty-eight".