669905965 has 8 divisors (see below), whose sum is σ = 817066008. Its totient is φ = 527138880.

The previous prime is 669905953. The next prime is 669906037. The reversal of 669905965 is 569509966.

It can be written as a sum of positive squares in 4 ways, for example, as 70341769 + 599564196 = 8387^2 + 24486^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 669905965 - 2¹¹ = 669903917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1097902 + ... + 1098511.

It is an arithmetic number, because the mean of its divisors is an integer number (102133251).

Almost surely, 2^669905965 is an apocalyptic number.

It is an amenable number.

669905965 is a deficient number, since it is larger than the sum of its proper divisors (147160043).

669905965 is a wasteful number, since it uses less digits than its factorization.

669905965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2196479.

The product of its (nonzero) digits is 3936600, while the sum is 55.

The square root of 669905965 is about 25882.5417028545. The cubic root of 669905965 is about 874.9930731424.

The spelling of 669905965 in words is "six hundred sixty-nine million, nine hundred five thousand, nine hundred sixty-five".