669543917 has 4 divisors (see below), whose sum is σ = 765193056. Its totient is φ = 573894780.

The previous prime is 669543913. The next prime is 669543947. The reversal of 669543917 is 719345966.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 669543917 - 2² = 669543913 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 (669543913) 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 3 ways as a sum of consecutive naturals, for example, 47824559 + ... + 47824572.

It is an arithmetic number, because the mean of its divisors is an integer number (191298264).

Almost surely, 2^669543917 is an apocalyptic number.

It is an amenable number.

669543917 is a deficient number, since it is larger than the sum of its proper divisors (95649139).

669543917 is an equidigital number, since it uses as much as digits as its factorization.

669543917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95649138.

The product of its digits is 1224720, while the sum is 50.

The square root of 669543917 is about 25875.5466995385. The cubic root of 669543917 is about 874.8354159015.

The spelling of 669543917 in words is "six hundred sixty-nine million, five hundred forty-three thousand, nine hundred seventeen".