669947 has 2 divisors, whose sum is σ = 669948. Its totient is φ = 669946.

The previous prime is 669943. The next prime is 669971. The reversal of 669947 is 749966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669947 - 2² = 669943 is a prime.

It is a Chen prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669947.

It is not a weakly prime, because it can be changed into another prime (669943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334973 + 334974.

It is an arithmetic number, because the mean of its divisors is an integer number (334974).

2⁶⁶⁹⁹⁴⁷ is an apocalyptic number.

669947 is a deficient number, since it is larger than the sum of its proper divisors (1).

669947 is an equidigital number, since it uses as much as digits as its factorization.

669947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 41.

The square root of 669947 is about 818.5029016442. The cubic root of 669947 is about 87.5010938639.

The spelling of 669947 in words is "six hundred sixty-nine thousand, nine hundred forty-seven".