669665489 has 4 divisors (see below), whose sum is σ = 670903860. Its totient is φ = 668427120.

The previous prime is 669665483. The next prime is 669665501. The reversal of 669665489 is 984566966.

669665489 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 426835600 + 242829889 = 20660^2 + 15583^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669665489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669665483) 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, 618374 + ... + 619455.

It is an arithmetic number, because the mean of its divisors is an integer number (167725965).

Almost surely, 2^669665489 is an apocalyptic number.

It is an amenable number.

669665489 is a deficient number, since it is larger than the sum of its proper divisors (1238371).

669665489 is a wasteful number, since it uses less digits than its factorization.

669665489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1238370.

The product of its digits is 16796160, while the sum is 59.

The square root of 669665489 is about 25877.8957606680. The cubic root of 669665489 is about 874.8883619204. Note that the first 3 decimals are identical.

The spelling of 669665489 in words is "six hundred sixty-nine million, six hundred sixty-five thousand, four hundred eighty-nine".