669405599 has 4 divisors (see below), whose sum is σ = 690999360. Its totient is φ = 647811840.

The previous prime is 669405557. The next prime is 669405601. The reversal of 669405599 is 995504966.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669405599 is a prime.

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 669405599.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669401599) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10796834 + ... + 10796895.

It is an arithmetic number, because the mean of its divisors is an integer number (172749840).

Almost surely, 2^669405599 is an apocalyptic number.

669405599 is a deficient number, since it is larger than the sum of its proper divisors (21593761).

669405599 is a wasteful number, since it uses less digits than its factorization.

669405599 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21593760.

The product of its (nonzero) digits is 2624400, while the sum is 53.

The square root of 669405599 is about 25872.8738063633. The cubic root of 669405599 is about 874.7751690102.

The spelling of 669405599 in words is "six hundred sixty-nine million, four hundred five thousand, five hundred ninety-nine".