664953871 has 2 divisors, whose sum is σ = 664953872. Its totient is φ = 664953870.

The previous prime is 664953859. The next prime is 664953917. The reversal of 664953871 is 178359466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664953871 - 2¹¹ = 664951823 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664953071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332476935 + 332476936.

It is an arithmetic number, because the mean of its divisors is an integer number (332476936).

Almost surely, 2^664953871 is an apocalyptic number.

664953871 is a deficient number, since it is larger than the sum of its proper divisors (1).

664953871 is an equidigital number, since it uses as much as digits as its factorization.

664953871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1088640, while the sum is 49.

The square root of 664953871 is about 25786.6994979970. The cubic root of 664953871 is about 872.8316907040.

The spelling of 664953871 in words is "six hundred sixty-four million, nine hundred fifty-three thousand, eight hundred seventy-one".