636740070557 has 2 divisors, whose sum is σ = 636740070558. Its totient is φ = 636740070556.

The previous prime is 636740070481. The next prime is 636740070601. The reversal of 636740070557 is 755070047636.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 635178714361 + 1561356196 = 796981^2 + 39514^2 .

It is a cyclic number.

It is not a de Polignac number, because 636740070557 - 2¹² = 636740066461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (636740070457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318370035278 + 318370035279.

It is an arithmetic number, because the mean of its divisors is an integer number (318370035279).

Almost surely, 2^636740070557 is an apocalyptic number.

It is an amenable number.

636740070557 is a deficient number, since it is larger than the sum of its proper divisors (1).

636740070557 is an equidigital number, since it uses as much as digits as its factorization.

636740070557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3704400, while the sum is 50.

The spelling of 636740070557 in words is "six hundred thirty-six billion, seven hundred forty million, seventy thousand, five hundred fifty-seven".