18180538 has 8 divisors (see below), whose sum is σ = 27340020. Its totient is φ = 9067200.

The previous prime is 18180527. The next prime is 18180541. The reversal of 18180538 is 83508181.

It can be written as a sum of positive squares in 2 ways, for example, as 11539609 + 6640929 = 3397^2 + 2577^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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 3 ways as a sum of consecutive naturals, for example, 10533 + ... + 12136.

Almost surely, 2^18180538 is an apocalyptic number.

18180538 is a deficient number, since it is larger than the sum of its proper divisors (9159482).

18180538 is a wasteful number, since it uses less digits than its factorization.

18180538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23072.

The product of its (nonzero) digits is 7680, while the sum is 34.

The square root of 18180538 is about 4263.8642098453. The cubic root of 18180538 is about 262.9474177673.

The spelling of 18180538 in words is "eighteen million, one hundred eighty thousand, five hundred thirty-eight".