18315812 has 6 divisors (see below), whose sum is σ = 32052678. Its totient is φ = 9157904.

The previous prime is 18315811. The next prime is 18315833. The reversal of 18315812 is 21851381.

It can be written as a sum of positive squares in only one way, i.e., 18028516 + 287296 = 4246^2 + 536^2 .

It is not an unprimeable number, because it can be changed into a prime (18315811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2289473 + ... + 2289480.

It is an arithmetic number, because the mean of its divisors is an integer number (5342113).

Almost surely, 2^18315812 is an apocalyptic number.

It is an amenable number.

18315812 is a deficient number, since it is larger than the sum of its proper divisors (13736866).

18315812 is a wasteful number, since it uses less digits than its factorization.

18315812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4578957 (or 4578955 counting only the distinct ones).

The product of its digits is 1920, while the sum is 29.

The square root of 18315812 is about 4279.6976528722. The cubic root of 18315812 is about 263.5979685807.

The spelling of 18315812 in words is "eighteen million, three hundred fifteen thousand, eight hundred twelve".