18025978 has 8 divisors (see below), whose sum is σ = 27698580. Its totient is φ = 8793120.

The previous prime is 18025961. The next prime is 18025991. The reversal of 18025978 is 87952081.

It can be written as a sum of positive squares in 2 ways, for example, as 16184529 + 1841449 = 4023^2 + 1357^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 18025978.

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, 109833 + ... + 109996.

Almost surely, 2^18025978 is an apocalyptic number.

18025978 is a deficient number, since it is larger than the sum of its proper divisors (9672602).

18025978 is a wasteful number, since it uses less digits than its factorization.

18025978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219872.

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 18025978 is about 4245.7011199565. The cubic root of 18025978 is about 262.2001558910.

The spelling of 18025978 in words is "eighteen million, twenty-five thousand, nine hundred seventy-eight".