18420800 has 84 divisors (see below), whose sum is σ = 47007780. Its totient is φ = 7096320.

The previous prime is 18420791. The next prime is 18420811. The reversal of 18420800 is 802481.

It can be written as a sum of positive squares in 6 ways, for example, as 33856 + 18386944 = 184^2 + 4288^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 46202 + ... + 46598.

Almost surely, 2^18420800 is an apocalyptic number.

18420800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18420800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23503890).

18420800 is an abundant number, since it is smaller than the sum of its proper divisors (28586980).

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

18420800 is a wasteful number, since it uses less digits than its factorization.

18420800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448 (or 433 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 23.

The square root of 18420800 is about 4291.9459456056. The cubic root of 18420800 is about 264.1006656202.

The spelling of 18420800 in words is "eighteen million, four hundred twenty thousand, eight hundred".