669745771 has 2 divisors, whose sum is σ = 669745772. Its totient is φ = 669745770.

The previous prime is 669745759. The next prime is 669745859. The reversal of 669745771 is 177547966.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669745771 is a prime.

It is not a weakly prime, because it can be changed into another prime (669745711) 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 as a sum of consecutive naturals, namely, 334872885 + 334872886.

It is an arithmetic number, because the mean of its divisors is an integer number (334872886).

Almost surely, 2^669745771 is an apocalyptic number.

669745771 is a deficient number, since it is larger than the sum of its proper divisors (1).

669745771 is an equidigital number, since it uses as much as digits as its factorization.

669745771 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2222640, while the sum is 52.

The square root of 669745771 is about 25879.4468835793. The cubic root of 669745771 is about 874.9233221515.

The spelling of 669745771 in words is "six hundred sixty-nine million, seven hundred forty-five thousand, seven hundred seventy-one".