20858856 has 16 divisors (see below), whose sum is σ = 52147200. Its totient is φ = 6952944.

The previous prime is 20858843. The next prime is 20858857. The reversal of 20858856 is 65885802.

It is not an unprimeable number, because it can be changed into a prime (20858857) 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, 434536 + ... + 434583.

It is an arithmetic number, because the mean of its divisors is an integer number (3259200).

Almost surely, 2^20858856 is an apocalyptic number.

It is an amenable number.

20858856 is an abundant number, since it is smaller than the sum of its proper divisors (31288344).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20858856 is a wasteful number, since it uses less digits than its factorization.

20858856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 869128 (or 869124 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 42.

The square root of 20858856 is about 4567.1496581566. The cubic root of 20858856 is about 275.2729235380.

The spelling of 20858856 in words is "twenty million, eight hundred fifty-eight thousand, eight hundred fifty-six".