665919431 has 8 divisors (see below), whose sum is σ = 690061680. Its totient is φ = 641855872.

The previous prime is 665919409. The next prime is 665919433. The reversal of 665919431 is 134919566.

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 665919431 - 2¹⁴ = 665903047 is a prime.

It is a super-2 number, since 2×665919431² = 886897377166727522, 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 (665919433) 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, 2165 + ... + 36558.

It is an arithmetic number, because the mean of its divisors is an integer number (86257710).

Almost surely, 2^665919431 is an apocalyptic number.

665919431 is a deficient number, since it is larger than the sum of its proper divisors (24142249).

665919431 is a wasteful number, since it uses less digits than its factorization.

665919431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39345.

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

The square root of 665919431 is about 25805.4147612473. The cubic root of 665919431 is about 873.2539574765.

The spelling of 665919431 in words is "six hundred sixty-five million, nine hundred nineteen thousand, four hundred thirty-one".