18202020 has 24 divisors (see below), whose sum is σ = 50965824. Its totient is φ = 4853856.

The previous prime is 18202003. The next prime is 18202033. The reversal of 18202020 is 2020281.

It is a Harshad number since it is a multiple of its sum of digits (15).

18202020 is a modest number, since divided by 2020 gives 1820 as remainder.

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 7 ways as a sum of consecutive naturals, for example, 151624 + ... + 151743.

It is an arithmetic number, because the mean of its divisors is an integer number (2123576).

Almost surely, 2^18202020 is an apocalyptic number.

18202020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18202020 is an abundant number, since it is smaller than the sum of its proper divisors (32763804).

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

18202020 is a wasteful number, since it uses less digits than its factorization.

18202020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303379 (or 303377 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 18202020 is about 4266.3825426232. The cubic root of 18202020 is about 263.0509426299.

The spelling of 18202020 in words is "eighteen million, two hundred two thousand, twenty".