669412169 has 2 divisors, whose sum is σ = 669412170. Its totient is φ = 669412168.

The previous prime is 669412147. The next prime is 669412241. The reversal of 669412169 is 961214966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 660490000 + 8922169 = 25700^2 + 2987^2 .

It is a cyclic number.

It is not a de Polignac number, because 669412169 - 2²⁸ = 400976713 is a prime.

It is a super-2 number, since 2×669412169² = 896225304010569122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (669412369) 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, 334706084 + 334706085.

It is an arithmetic number, because the mean of its divisors is an integer number (334706085).

Almost surely, 2^669412169 is an apocalyptic number.

It is an amenable number.

669412169 is a deficient number, since it is larger than the sum of its proper divisors (1).

669412169 is an equidigital number, since it uses as much as digits as its factorization.

669412169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 44.

The square root of 669412169 is about 25873.0007730066. Note that the first 3 decimals coincide. The cubic root of 669412169 is about 874.7780308795.

The spelling of 669412169 in words is "six hundred sixty-nine million, four hundred twelve thousand, one hundred sixty-nine".