665431199 has 6 divisors (see below), whose sum is σ = 683903304. Its totient is φ = 647445240.

The previous prime is 665431183. The next prime is 665431211. The reversal of 665431199 is 991134566.

It is not a de Polignac number, because 665431199 - 2⁴ = 665431183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665431159) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 241667 + ... + 244404.

It is an arithmetic number, because the mean of its divisors is an integer number (113983884).

Almost surely, 2^665431199 is an apocalyptic number.

665431199 is a deficient number, since it is larger than the sum of its proper divisors (18472105).

665431199 is an equidigital number, since it uses as much as digits as its factorization.

665431199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 486145 (or 486108 counting only the distinct ones).

The product of its digits is 174960, while the sum is 44.

The square root of 665431199 is about 25795.9531516089. The cubic root of 665431199 is about 873.0404908294.

The spelling of 665431199 in words is "six hundred sixty-five million, four hundred thirty-one thousand, one hundred ninety-nine".