18131393 has 8 divisors (see below), whose sum is σ = 20755200. Its totient is φ = 15516000.

The previous prime is 18131381. The next prime is 18131411. The reversal of 18131393 is 39313181.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18131393 - 2⁸ = 18131137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18131303) 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, 3533 + ... + 6981.

It is an arithmetic number, because the mean of its divisors is an integer number (2594400).

Almost surely, 2^18131393 is an apocalyptic number.

It is an amenable number.

18131393 is a deficient number, since it is larger than the sum of its proper divisors (2623807).

18131393 is an equidigital number, since it uses as much as digits as its factorization.

18131393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4207.

The product of its digits is 1944, while the sum is 29.

The square root of 18131393 is about 4258.0973450592. The cubic root of 18131393 is about 262.7102738446.

The spelling of 18131393 in words is "eighteen million, one hundred thirty-one thousand, three hundred ninety-three".