669441947 has 2 divisors, whose sum is σ = 669441948. Its totient is φ = 669441946.

The previous prime is 669441943. The next prime is 669441961. The reversal of 669441947 is 749144966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669441947 - 2² = 669441943 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 669441895 and 669441904.

It is not a weakly prime, because it can be changed into another prime (669441943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334720973 + 334720974.

It is an arithmetic number, because the mean of its divisors is an integer number (334720974).

Almost surely, 2^669441947 is an apocalyptic number.

669441947 is a deficient number, since it is larger than the sum of its proper divisors (1).

669441947 is an equidigital number, since it uses as much as digits as its factorization.

669441947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 50.

The square root of 669441947 is about 25873.5762313601. The cubic root of 669441947 is about 874.7910018388.

The spelling of 669441947 in words is "six hundred sixty-nine million, four hundred forty-one thousand, nine hundred forty-seven".