636910009091 has 2 divisors, whose sum is σ = 636910009092. Its totient is φ = 636910009090.

The previous prime is 636910009051. The next prime is 636910009171. The reversal of 636910009091 is 190900019636.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 636910009091 - 2¹⁰ = 636910008067 is a prime.

It is not a weakly prime, because it can be changed into another prime (636910009051) 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, 318455004545 + 318455004546.

It is an arithmetic number, because the mean of its divisors is an integer number (318455004546).

Almost surely, 2^636910009091 is an apocalyptic number.

636910009091 is a deficient number, since it is larger than the sum of its proper divisors (1).

636910009091 is an equidigital number, since it uses as much as digits as its factorization.

636910009091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 78732, while the sum is 44.

The spelling of 636910009091 in words is "six hundred thirty-six billion, nine hundred ten million, nine thousand, ninety-one".