285181920 has 72 divisors (see below), whose sum is σ = 973188216. Its totient is φ = 76048128.

The previous prime is 285181907. The next prime is 285181931. The reversal of 285181920 is 29181582.

285181920 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 97582 + ... + 100461.

It is an arithmetic number, because the mean of its divisors is an integer number (13516503).

Almost surely, 2^285181920 is an apocalyptic number.

285181920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

285181920 is an abundant number, since it is smaller than the sum of its proper divisors (688006296).

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

285181920 is a wasteful number, since it uses less digits than its factorization.

285181920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198064 (or 198053 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 285181920 is about 16887.3301619883. The cubic root of 285181920 is about 658.2244286375.

The spelling of 285181920 in words is "two hundred eighty-five million, one hundred eighty-one thousand, nine hundred twenty".