636681011 has 2 divisors, whose sum is σ = 636681012. Its totient is φ = 636681010.

The previous prime is 636680999. The next prime is 636681029. The reversal of 636681011 is 110186636.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 636681011 - 2²⁶ = 569572147 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (636681511) 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, 318340505 + 318340506.

It is an arithmetic number, because the mean of its divisors is an integer number (318340506).

Almost surely, 2^636681011 is an apocalyptic number.

636681011 is a deficient number, since it is larger than the sum of its proper divisors (1).

636681011 is an equidigital number, since it uses as much as digits as its factorization.

636681011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 636681011 is about 25232.5387347369. The cubic root of 636681011 is about 860.2815965353.

The spelling of 636681011 in words is "six hundred thirty-six million, six hundred eighty-one thousand, eleven".