669406431 has 4 divisors (see below), whose sum is σ = 892541912. Its totient is φ = 446270952.

The previous prime is 669406417. The next prime is 669406453. The reversal of 669406431 is 134604966.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 669406431 - 2¹⁴ = 669390047 is a prime.

It is a super-2 number, since 2×669406431² = 896209939728315522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 669406431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669406481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111567736 + ... + 111567741.

It is an arithmetic number, because the mean of its divisors is an integer number (223135478).

Almost surely, 2^669406431 is an apocalyptic number.

669406431 is a deficient number, since it is larger than the sum of its proper divisors (223135481).

669406431 is a wasteful number, since it uses less digits than its factorization.

669406431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223135480.

The product of its (nonzero) digits is 93312, while the sum is 39.

The square root of 669406431 is about 25872.8898849742. The cubic root of 669406431 is about 874.7755314276.

The spelling of 669406431 in words is "six hundred sixty-nine million, four hundred six thousand, four hundred thirty-one".