667699 has 2 divisors, whose sum is σ = 667700. Its totient is φ = 667698.

The previous prime is 667697. The next prime is 667727. The reversal of 667699 is 996766.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 667699 - 2¹ = 667697 is a prime.

Together with 667697, it forms a pair of twin primes.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 667699.

It is not a weakly prime, because it can be changed into another prime (667691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333849 + 333850.

It is an arithmetic number, because the mean of its divisors is an integer number (333850).

2⁶⁶⁷⁶⁹⁹ is an apocalyptic number.

667699 is a deficient number, since it is larger than the sum of its proper divisors (1).

667699 is an equidigital number, since it uses as much as digits as its factorization.

667699 is an evil number, because the sum of its binary digits is even.

The product of its digits is 122472, while the sum is 43.

The square root of 667699 is about 817.1285088650. The cubic root of 667699 is about 87.4031145307.

The spelling of 667699 in words is "six hundred sixty-seven thousand, six hundred ninety-nine".