20318990 has 16 divisors (see below), whose sum is σ = 36648720. Its totient is φ = 8111040.

The previous prime is 20318989. The next prime is 20319007. The reversal of 20318990 is 9981302.

It is a super-2 number, since 2×20318990² = 825722709240200, which contains 22 as substring.

It is a Curzon number.

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, 3905 + ... + 7475.

It is an arithmetic number, because the mean of its divisors is an integer number (2290545).

Almost surely, 2^20318990 is an apocalyptic number.

20318990 is a deficient number, since it is larger than the sum of its proper divisors (16329730).

20318990 is a wasteful number, since it uses less digits than its factorization.

20318990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4147.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 20318990 is about 4507.6590376824. The cubic root of 20318990 is about 272.8772767061.

The spelling of 20318990 in words is "twenty million, three hundred eighteen thousand, nine hundred ninety".