669615971 has 4 divisors (see below), whose sum is σ = 680593344. Its totient is φ = 658638600.

The previous prime is 669615949. The next prime is 669616007. The reversal of 669615971 is 179516966.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669615971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669615911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5488595 + ... + 5488716.

It is an arithmetic number, because the mean of its divisors is an integer number (170148336).

Almost surely, 2^669615971 is an apocalyptic number.

669615971 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

669615971 is a deficient number, since it is larger than the sum of its proper divisors (10977373).

669615971 is a wasteful number, since it uses less digits than its factorization.

669615971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10977372.

The product of its digits is 612360, while the sum is 50.

The square root of 669615971 is about 25876.9389804899. The cubic root of 669615971 is about 874.8667970294.

The spelling of 669615971 in words is "six hundred sixty-nine million, six hundred fifteen thousand, nine hundred seventy-one".