664685299 has 2 divisors, whose sum is σ = 664685300. Its totient is φ = 664685298.

The previous prime is 664685297. The next prime is 664685309. The reversal of 664685299 is 992586466.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664685299 - 2¹ = 664685297 is a prime.

Together with 664685297, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (664685293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332342649 + 332342650.

It is an arithmetic number, because the mean of its divisors is an integer number (332342650).

Almost surely, 2^664685299 is an apocalyptic number.

664685299 is a deficient number, since it is larger than the sum of its proper divisors (1).

664685299 is an equidigital number, since it uses as much as digits as its factorization.

664685299 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5598720, while the sum is 55.

The square root of 664685299 is about 25781.4914037183. The cubic root of 664685299 is about 872.7141638949.

The spelling of 664685299 in words is "six hundred sixty-four million, six hundred eighty-five thousand, two hundred ninety-nine".