18317920 has 24 divisors (see below), whose sum is σ = 43276464. Its totient is φ = 7327104.

The previous prime is 18317917. The next prime is 18317927. The reversal of 18317920 is 2971381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18317927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57084 + ... + 57403.

It is an arithmetic number, because the mean of its divisors is an integer number (1803186).

Almost surely, 2^18317920 is an apocalyptic number.

18317920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18317920 is an abundant number, since it is smaller than the sum of its proper divisors (24958544).

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

18317920 is a wasteful number, since it uses less digits than its factorization.

18317920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114502 (or 114494 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 18317920 is about 4279.9439248663. The cubic root of 18317920 is about 263.6080808488.

The spelling of 18317920 in words is "eighteen million, three hundred seventeen thousand, nine hundred twenty".