18084820 has 24 divisors (see below), whose sum is σ = 40900104. Its totient is φ = 6677376.

The previous prime is 18084799. The next prime is 18084851. The reversal of 18084820 is 2848081.

It can be written as a sum of positive squares in 4 ways, for example, as 1077444 + 17007376 = 1038^2 + 4124^2 .

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, 34519 + ... + 35038.

It is an arithmetic number, because the mean of its divisors is an integer number (1704171).

Almost surely, 2^18084820 is an apocalyptic number.

18084820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18084820 is an abundant number, since it is smaller than the sum of its proper divisors (22815284).

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

18084820 is a wasteful number, since it uses less digits than its factorization.

18084820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69579 (or 69577 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 31.

The square root of 18084820 is about 4252.6250716469. The cubic root of 18084820 is about 262.4851450399.

The spelling of 18084820 in words is "eighteen million, eighty-four thousand, eight hundred twenty".