18031525 has 6 divisors (see below), whose sum is σ = 22359122. Its totient is φ = 14425200.

The previous prime is 18031483. The next prime is 18031547. The reversal of 18031525 is 52513081.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 315844 + 17715681 = 562^2 + 4209^2 .

It is not a de Polignac number, because 18031525 - 2¹¹ = 18029477 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 721261 = 18031525 / (1 + 8 + 0 + 3 + 1 + 5 + 2 + 5).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18031525.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 360606 + ... + 360655.

Almost surely, 2^18031525 is an apocalyptic number.

It is an amenable number.

18031525 is a deficient number, since it is larger than the sum of its proper divisors (4327597).

18031525 is an equidigital number, since it uses as much as digits as its factorization.

18031525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 721271 (or 721266 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 18031525 is about 4246.3543187068. The cubic root of 18031525 is about 262.2270481000.

The spelling of 18031525 in words is "eighteen million, thirty-one thousand, five hundred twenty-five".