669919605 has 16 divisors (see below), whose sum is σ = 1085441280. Its totient is φ = 352767168.

The previous prime is 669919603. The next prime is 669919609. The reversal of 669919605 is 506919966.

It is not a de Polignac number, because 669919605 - 2¹ = 669919603 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669919603) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 281482 + ... + 283851.

It is an arithmetic number, because the mean of its divisors is an integer number (67840080).

Almost surely, 2^669919605 is an apocalyptic number.

It is an amenable number.

669919605 is a deficient number, since it is larger than the sum of its proper divisors (415521675).

669919605 is a wasteful number, since it uses less digits than its factorization.

669919605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565420.

The product of its (nonzero) digits is 787320, while the sum is 51.

The square root of 669919605 is about 25882.8051995915. The cubic root of 669919605 is about 874.9990116996. Note that the first 3 decimals are identical.

The spelling of 669919605 in words is "six hundred sixty-nine million, nine hundred nineteen thousand, six hundred five".