669745859 has 2 divisors, whose sum is σ = 669745860. Its totient is φ = 669745858.

The previous prime is 669745771. The next prime is 669745903. The reversal of 669745859 is 958547966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 669745859 - 2⁸ = 669745603 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 669745798 and 669745807.

It is not a weakly prime, because it can be changed into another prime (669745759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334872929 + 334872930.

It is an arithmetic number, because the mean of its divisors is an integer number (334872930).

Almost surely, 2^669745859 is an apocalyptic number.

669745859 is a deficient number, since it is larger than the sum of its proper divisors (1).

669745859 is an equidigital number, since it uses as much as digits as its factorization.

669745859 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16329600, while the sum is 59.

The square root of 669745859 is about 25879.4485837701. The cubic root of 669745859 is about 874.9233604712.

The spelling of 669745859 in words is "six hundred sixty-nine million, seven hundred forty-five thousand, eight hundred fifty-nine".