669798909 has 16 divisors (see below), whose sum is σ = 1068625600. Its totient is φ = 412183728.

The previous prime is 669798907. The next prime is 669798949. The reversal of 669798909 is 909897966.

It is not a de Polignac number, because 669798909 - 2¹ = 669798907 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669798907) 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 15 ways as a sum of consecutive naturals, for example, 953779 + ... + 954480.

It is an arithmetic number, because the mean of its divisors is an integer number (66789100).

Almost surely, 2^669798909 is an apocalyptic number.

It is an amenable number.

669798909 is a deficient number, since it is larger than the sum of its proper divisors (398826691).

669798909 is a wasteful number, since it uses less digits than its factorization.

669798909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1908281 (or 1908275 counting only the distinct ones).

The product of its (nonzero) digits is 13226976, while the sum is 63.

The square root of 669798909 is about 25880.4735080330. The cubic root of 669798909 is about 874.9464605064.

The spelling of 669798909 in words is "six hundred sixty-nine million, seven hundred ninety-eight thousand, nine hundred nine".