18186880 has 64 divisors (see below), whose sum is σ = 43996680. Its totient is φ = 7188480.

The previous prime is 18186871. The next prime is 18186881. The reversal of 18186880 is 8868181.

It can be written as a sum of positive squares in 4 ways, for example, as 6843456 + 11343424 = 2616^2 + 3368^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (18186881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100390 + ... + 100570.

Almost surely, 2^18186880 is an apocalyptic number.

18186880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18186880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21998340).

18186880 is an abundant number, since it is smaller than the sum of its proper divisors (25809800).

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

18186880 is a wasteful number, since it uses less digits than its factorization.

18186880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357 (or 345 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 40.

The square root of 18186880 is about 4264.6078366012. The cubic root of 18186880 is about 262.9779892619.

The spelling of 18186880 in words is "eighteen million, one hundred eighty-six thousand, eight hundred eighty".