665344431 has 12 divisors (see below), whose sum is σ = 963408160. Its totient is φ = 442476000.

The previous prime is 665344429. The next prime is 665344441. The reversal of 665344431 is 134443566.

It is not a de Polignac number, because 665344431 - 2¹ = 665344429 is a prime.

It is a super-2 number, since 2×665344431² = 885366423725427522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665344441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 86695 + ... + 94056.

Almost surely, 2^665344431 is an apocalyptic number.

665344431 is a deficient number, since it is larger than the sum of its proper divisors (298063729).

665344431 is a wasteful number, since it uses less digits than its factorization.

665344431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181166 (or 181163 counting only the distinct ones).

The product of its digits is 103680, while the sum is 36.

The square root of 665344431 is about 25794.2712825930. The cubic root of 665344431 is about 873.0025428692.

Adding to 665344431 its reverse (134443566), we get a palindrome (799787997).

The spelling of 665344431 in words is "six hundred sixty-five million, three hundred forty-four thousand, four hundred thirty-one".