669879539 has 6 divisors (see below), whose sum is σ = 779247684. Its totient is φ = 574182420.

The previous prime is 669879517. The next prime is 669879619. The reversal of 669879539 is 935978966.

It is not a de Polignac number, because 669879539 - 2²⁰ = 668830963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669879239) 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 5 ways as a sum of consecutive naturals, for example, 6835457 + ... + 6835554.

It is an arithmetic number, because the mean of its divisors is an integer number (129874614).

Almost surely, 2^669879539 is an apocalyptic number.

669879539 is a deficient number, since it is larger than the sum of its proper divisors (109368145).

669879539 is a wasteful number, since it uses less digits than its factorization.

669879539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13671025 (or 13671018 counting only the distinct ones).

The product of its digits is 22044960, while the sum is 62.

The square root of 669879539 is about 25882.0311992703. The cubic root of 669879539 is about 874.9815676117.

The spelling of 669879539 in words is "six hundred sixty-nine million, eight hundred seventy-nine thousand, five hundred thirty-nine".