18186240 has 128 divisors (see below), whose sum is σ = 59767920. Its totient is φ = 4718592.

The previous prime is 18186199. The next prime is 18186263. The reversal of 18186240 is 4268181.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18186198 and 18186207.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 491502 + ... + 491538.

Almost surely, 2^18186240 is an apocalyptic number.

18186240 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 18186240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29883960).

18186240 is an abundant number, since it is smaller than the sum of its proper divisors (41581680).

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

18186240 is an frugal number, since it uses more digits than its factorization.

18186240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 18186240 is about 4264.5327997332. The cubic root of 18186240 is about 262.9749044761.

The spelling of 18186240 in words is "eighteen million, one hundred eighty-six thousand, two hundred forty".