18315620 has 48 divisors (see below), whose sum is σ = 40877760. Its totient is φ = 6873984.

The previous prime is 18315607. The next prime is 18315631. The reversal of 18315620 is 2651381.

It is a self number, because there is not a number n which added to its sum of digits gives 18315620.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59507 + ... + 59813.

It is an arithmetic number, because the mean of its divisors is an integer number (851620).

Almost surely, 2^18315620 is an apocalyptic number.

18315620 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 18315620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20438880).

18315620 is an abundant number, since it is smaller than the sum of its proper divisors (22562140).

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

18315620 is a wasteful number, since it uses less digits than its factorization.

18315620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492 (or 490 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 18315620 is about 4279.6752213223. The cubic root of 18315620 is about 263.5970475007.

The spelling of 18315620 in words is "eighteen million, three hundred fifteen thousand, six hundred twenty".