18505020 has 48 divisors (see below), whose sum is σ = 52133760. Its totient is φ = 4904256.

The previous prime is 18505013. The next prime is 18505037. The reversal of 18505020 is 2050581.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9879 + ... + 11601.

It is an arithmetic number, because the mean of its divisors is an integer number (1086120).

Almost surely, 2^18505020 is an apocalyptic number.

18505020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18505020 is an abundant number, since it is smaller than the sum of its proper divisors (33628740).

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

18505020 is a wasteful number, since it uses less digits than its factorization.

18505020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1914 (or 1912 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 21.

The square root of 18505020 is about 4301.7461570855. The cubic root of 18505020 is about 264.5025436819.

The spelling of 18505020 in words is "eighteen million, five hundred five thousand, twenty".