18057397 has 4 divisors (see below), whose sum is σ = 18275040. Its totient is φ = 17839756.

The previous prime is 18057379. The next prime is 18057419. The reversal of 18057397 is 79375081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79375081 = 1213 ⋅65437.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18057397 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18057307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108697 + ... + 108862.

It is an arithmetic number, because the mean of its divisors is an integer number (4568760).

Almost surely, 2^18057397 is an apocalyptic number.

It is an amenable number.

18057397 is a deficient number, since it is larger than the sum of its proper divisors (217643).

18057397 is an equidigital number, since it uses as much as digits as its factorization.

18057397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217642.

The product of its (nonzero) digits is 52920, while the sum is 40.

The square root of 18057397 is about 4249.3996046500. The cubic root of 18057397 is about 262.3524044043.

The spelling of 18057397 in words is "eighteen million, fifty-seven thousand, three hundred ninety-seven".