20813487868 has 24 divisors (see below), whose sum is σ = 36775942784. Its totient is φ = 10306494000.

The previous prime is 20813487857. The next prime is 20813487899. The reversal of 20813487868 is 86878431802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 147871 + ... + 251977.

Almost surely, 2^20813487868 is an apocalyptic number.

It is an amenable number.

20813487868 is a deficient number, since it is larger than the sum of its proper divisors (15962454916).

20813487868 is a wasteful number, since it uses less digits than its factorization.

20813487868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104593 (or 104591 counting only the distinct ones).

The product of its (nonzero) digits is 4128768, while the sum is 55.

The spelling of 20813487868 in words is "twenty billion, eight hundred thirteen million, four hundred eighty-seven thousand, eight hundred sixty-eight".