669887973 has 6 divisors (see below), whose sum is σ = 967615974. Its totient is φ = 446591976.

The previous prime is 669887969. The next prime is 669887987. The reversal of 669887973 is 379788966.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 559700964 + 110187009 = 23658^2 + 10497^2 .

It is not a de Polignac number, because 669887973 - 2² = 669887969 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 669887973.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669887963) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 37215990 + ... + 37216007.

It is an arithmetic number, because the mean of its divisors is an integer number (161269329).

Almost surely, 2^669887973 is an apocalyptic number.

It is an amenable number.

669887973 is a deficient number, since it is larger than the sum of its proper divisors (297728001).

669887973 is a wasteful number, since it uses less digits than its factorization.

669887973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74432003 (or 74432000 counting only the distinct ones).

The product of its digits is 27433728, while the sum is 63.

The square root of 669887973 is about 25882.1941303283. The cubic root of 669887973 is about 874.9852396966.

The spelling of 669887973 in words is "six hundred sixty-nine million, eight hundred eighty-seven thousand, nine hundred seventy-three".