18317640 has 64 divisors (see below), whose sum is σ = 59952960. Its totient is φ = 4440320.

The previous prime is 18317609. The next prime is 18317681. The reversal of 18317640 is 4671381.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18317598 and 18317607.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5619 + ... + 8258.

It is an arithmetic number, because the mean of its divisors is an integer number (936765).

Almost surely, 2^18317640 is an apocalyptic number.

18317640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18317640 is an abundant number, since it is smaller than the sum of its proper divisors (41635320).

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

18317640 is a wasteful number, since it uses less digits than its factorization.

18317640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13902 (or 13898 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 18317640 is about 4279.9112140324. The cubic root of 18317640 is about 263.6067377079.

The spelling of 18317640 in words is "eighteen million, three hundred seventeen thousand, six hundred forty".