660634518757 has 2 divisors, whose sum is σ = 660634518758. Its totient is φ = 660634518756.

The previous prime is 660634518623. The next prime is 660634518779. The reversal of 660634518757 is 757815436066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 597074562436 + 63559956321 = 772706^2 + 252111^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660634518757 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (660634518457) 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, 330317259378 + 330317259379.

It is an arithmetic number, because the mean of its divisors is an integer number (330317259379).

Almost surely, 2^660634518757 is an apocalyptic number.

It is an amenable number.

660634518757 is a deficient number, since it is larger than the sum of its proper divisors (1).

660634518757 is an equidigital number, since it uses as much as digits as its factorization.

660634518757 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25401600, while the sum is 58.

The spelling of 660634518757 in words is "six hundred sixty billion, six hundred thirty-four million, five hundred eighteen thousand, seven hundred fifty-seven".