851864820 has 24 divisors (see below), whose sum is σ = 2385221664. Its totient is φ = 227163936.

The previous prime is 851864807. The next prime is 851864861. The reversal of 851864820 is 28468158.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7098814 + ... + 7098933.

It is an arithmetic number, because the mean of its divisors is an integer number (99384236).

Almost surely, 2^851864820 is an apocalyptic number.

It is an amenable number.

851864820 is an abundant number, since it is smaller than the sum of its proper divisors (1533356844).

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

851864820 is a wasteful number, since it uses less digits than its factorization.

851864820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14197759 (or 14197757 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 42.

The square root of 851864820 is about 29186.7233515515. The cubic root of 851864820 is about 947.9604703202.

The spelling of 851864820 in words is "eight hundred fifty-one million, eight hundred sixty-four thousand, eight hundred twenty".