18521020 has 36 divisors (see below), whose sum is σ = 45246600. Its totient is φ = 6349728.

The previous prime is 18520993. The next prime is 18521021. The reversal of 18521020 is 2012581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18521021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8470 + ... + 10429.

It is an arithmetic number, because the mean of its divisors is an integer number (1256850).

Almost surely, 2^18521020 is an apocalyptic number.

18521020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18521020 is an abundant number, since it is smaller than the sum of its proper divisors (26725580).

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

18521020 is a wasteful number, since it uses less digits than its factorization.

18521020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18922 (or 18913 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 18521020 is about 4303.6054651885. The cubic root of 18521020 is about 264.5787540214.

The spelling of 18521020 in words is "eighteen million, five hundred twenty-one thousand, twenty".