664365852691 has 2 divisors, whose sum is σ = 664365852692. Its totient is φ = 664365852690.

The previous prime is 664365852649. The next prime is 664365852719. The reversal of 664365852691 is 196258563466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664365852691 - 2¹⁷ = 664365721619 is a prime.

It is not a weakly prime, because it can be changed into another prime (664365852391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332182926345 + 332182926346.

It is an arithmetic number, because the mean of its divisors is an integer number (332182926346).

Almost surely, 2^664365852691 is an apocalyptic number.

664365852691 is a deficient number, since it is larger than the sum of its proper divisors (1).

664365852691 is an equidigital number, since it uses as much as digits as its factorization.

664365852691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 55987200, while the sum is 61.

The spelling of 664365852691 in words is "six hundred sixty-four billion, three hundred sixty-five million, eight hundred fifty-two thousand, six hundred ninety-one".