18431340 has 24 divisors (see below), whose sum is σ = 51607920. Its totient is φ = 4915008.

The previous prime is 18431339. The next prime is 18431341. The reversal of 18431340 is 4313481.

It is an interprime number because it is at equal distance from previous prime (18431339) and next prime (18431341).

It is a self number, because there is not a number n which added to its sum of digits gives 18431340.

It is not an unprimeable number, because it can be changed into a prime (18431341) 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 7 ways as a sum of consecutive naturals, for example, 153535 + ... + 153654.

It is an arithmetic number, because the mean of its divisors is an integer number (2150330).

Almost surely, 2^18431340 is an apocalyptic number.

18431340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18431340 is an abundant number, since it is smaller than the sum of its proper divisors (33176580).

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

18431340 is a wasteful number, since it uses less digits than its factorization.

18431340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307201 (or 307199 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 18431340 is about 4293.1736512748. The cubic root of 18431340 is about 264.1510269920.

The spelling of 18431340 in words is "eighteen million, four hundred thirty-one thousand, three hundred forty".