20812887 has 24 divisors (see below), whose sum is σ = 30750720. Its totient is φ = 13562640.

The previous prime is 20812877. The next prime is 20812889. The reversal of 20812887 is 78821802.

It is not a de Polignac number, because 20812887 - 2⁶ = 20812823 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20812889) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 149664 + ... + 149802.

It is an arithmetic number, because the mean of its divisors is an integer number (1281280).

Almost surely, 2^20812887 is an apocalyptic number.

20812887 is a deficient number, since it is larger than the sum of its proper divisors (9937833).

20812887 is a wasteful number, since it uses less digits than its factorization.

20812887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 36.

The square root of 20812887 is about 4562.1143124652. The cubic root of 20812887 is about 275.0705582035.

The spelling of 20812887 in words is "twenty million, eight hundred twelve thousand, eight hundred eighty-seven".