18255990 has 32 divisors (see below), whose sum is σ = 44051040. Its totient is φ = 4841984.

The previous prime is 18255989. The next prime is 18256003. The reversal of 18255990 is 9955281.

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 15 ways as a sum of consecutive naturals, for example, 4366 + ... + 7454.

It is an arithmetic number, because the mean of its divisors is an integer number (1376595).

Almost surely, 2^18255990 is an apocalyptic number.

18255990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18255990 is an abundant number, since it is smaller than the sum of its proper divisors (25795050).

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

18255990 is a wasteful number, since it uses less digits than its factorization.

18255990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3296.

The product of its (nonzero) digits is 32400, while the sum is 39.

The square root of 18255990 is about 4272.7028916132. The cubic root of 18255990 is about 263.3106729775.

The spelling of 18255990 in words is "eighteen million, two hundred fifty-five thousand, nine hundred ninety".