18188340 has 24 divisors (see below), whose sum is σ = 50927520. Its totient is φ = 4850208.

The previous prime is 18188329. The next prime is 18188341. The reversal of 18188340 is 4388181.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18188341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151510 + ... + 151629.

It is an arithmetic number, because the mean of its divisors is an integer number (2121980).

Almost surely, 2^18188340 is an apocalyptic number.

18188340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18188340 is an abundant number, since it is smaller than the sum of its proper divisors (32739180).

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

18188340 is a wasteful number, since it uses less digits than its factorization.

18188340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303151 (or 303149 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 33.

The square root of 18188340 is about 4264.7790095150. The cubic root of 18188340 is about 262.9850261586.

It can be divided in two parts, 18188 and 340, that added together give a triangular number (18528 = T₁₉₂).

The spelling of 18188340 in words is "eighteen million, one hundred eighty-eight thousand, three hundred forty".