18531340 has 12 divisors (see below), whose sum is σ = 38915856. Its totient is φ = 7412528.

The previous prime is 18531311. The next prime is 18531347. The reversal of 18531340 is 4313581.

It is not an unprimeable number, because it can be changed into a prime (18531347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 463264 + ... + 463303.

It is an arithmetic number, because the mean of its divisors is an integer number (3242988).

Almost surely, 2^18531340 is an apocalyptic number.

18531340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18531340 is an abundant number, since it is smaller than the sum of its proper divisors (20384516).

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

18531340 is a wasteful number, since it uses less digits than its factorization.

18531340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 926576 (or 926574 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 18531340 is about 4304.8042928802. The cubic root of 18531340 is about 264.6278864082.

The spelling of 18531340 in words is "eighteen million, five hundred thirty-one thousand, three hundred forty".