18180978 has 8 divisors (see below), whose sum is σ = 36361968. Its totient is φ = 6060324.

The previous prime is 18180937. The next prime is 18180979. The reversal of 18180978 is 87908181.

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

18180978 is an admirable number.

It is a super-2 number, since 2×18180978² = 661095922072968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18180979) by changing a digit.

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, 1515076 + ... + 1515087.

It is an arithmetic number, because the mean of its divisors is an integer number (4545246).

Almost surely, 2^18180978 is an apocalyptic number.

18180978 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18180978 is a wasteful number, since it uses less digits than its factorization.

18180978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3030168.

The product of its (nonzero) digits is 32256, while the sum is 42.

The square root of 18180978 is about 4263.9158059230. The cubic root of 18180978 is about 262.9495390087.

The spelling of 18180978 in words is "eighteen million, one hundred eighty thousand, nine hundred seventy-eight".