18431797 has 2 divisors, whose sum is σ = 18431798. Its totient is φ = 18431796.

The previous prime is 18431789. The next prime is 18431807. The reversal of 18431797 is 79713481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18369796 + 62001 = 4286^2 + 249^2 .

It is a cyclic number.

It is not a de Polignac number, because 18431797 - 2³ = 18431789 is a prime.

It is a super-2 number, since 2×18431797² = 679462281298418, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18431297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9215898 + 9215899.

It is an arithmetic number, because the mean of its divisors is an integer number (9215899).

Almost surely, 2^18431797 is an apocalyptic number.

It is an amenable number.

18431797 is a deficient number, since it is larger than the sum of its proper divisors (1).

18431797 is an equidigital number, since it uses as much as digits as its factorization.

18431797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 40.

The square root of 18431797 is about 4293.2268749741. The cubic root of 18431797 is about 264.1532101580.

The spelling of 18431797 in words is "eighteen million, four hundred thirty-one thousand, seven hundred ninety-seven".