18402420 has 24 divisors (see below), whose sum is σ = 51526944. Its totient is φ = 4907296.

The previous prime is 18402413. The next prime is 18402457. The reversal of 18402420 is 2420481.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153294 + ... + 153413.

It is an arithmetic number, because the mean of its divisors is an integer number (2146956).

Almost surely, 2^18402420 is an apocalyptic number.

18402420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18402420 is an abundant number, since it is smaller than the sum of its proper divisors (33124524).

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

18402420 is a wasteful number, since it uses less digits than its factorization.

18402420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306719 (or 306717 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

The square root of 18402420 is about 4289.8041913355. The cubic root of 18402420 is about 264.0127978185.

The spelling of 18402420 in words is "eighteen million, four hundred two thousand, four hundred twenty".