18102978 has 48 divisors (see below), whose sum is σ = 41558400. Its totient is φ = 5683392.

The previous prime is 18102949. The next prime is 18102983. The reversal of 18102978 is 87920181.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29923 + ... + 30521.

It is an arithmetic number, because the mean of its divisors is an integer number (865800).

Almost surely, 2^18102978 is an apocalyptic number.

18102978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18102978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20779200).

18102978 is an abundant number, since it is smaller than the sum of its proper divisors (23455422).

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

18102978 is a wasteful number, since it uses less digits than its factorization.

18102978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703 (or 700 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 18102978 is about 4254.7594526600. The cubic root of 18102978 is about 262.5729647508.

The spelling of 18102978 in words is "eighteen million, one hundred two thousand, nine hundred seventy-eight".