18312265 has 4 divisors (see below), whose sum is σ = 21974724. Its totient is φ = 14649808.

The previous prime is 18312263. The next prime is 18312319. The reversal of 18312265 is 56221381.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5294601 + 13017664 = 2301^2 + 3608^2 .

It is a cyclic number.

It is not a de Polignac number, because 18312265 - 2¹ = 18312263 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18312263) 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, 1831222 + ... + 1831231.

It is an arithmetic number, because the mean of its divisors is an integer number (5493681).

Almost surely, 2^18312265 is an apocalyptic number.

It is an amenable number.

18312265 is a deficient number, since it is larger than the sum of its proper divisors (3662459).

18312265 is an equidigital number, since it uses as much as digits as its factorization.

18312265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3662458.

The product of its digits is 2880, while the sum is 28.

The square root of 18312265 is about 4279.2832343747. The cubic root of 18312265 is about 263.5809515473.

It can be divided in two parts, 1831 and 2265, that added together give a 12-th power (4096 = 2¹²).

The spelling of 18312265 in words is "eighteen million, three hundred twelve thousand, two hundred sixty-five".