636630173 has 2 divisors, whose sum is σ = 636630174. Its totient is φ = 636630172.

The previous prime is 636630157. The next prime is 636630191. The reversal of 636630173 is 371036636.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 540237049 + 96393124 = 23243^2 + 9818^2 .

It is a cyclic number.

It is not a de Polignac number, because 636630173 - 2⁴ = 636630157 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (636630193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318315086 + 318315087.

It is an arithmetic number, because the mean of its divisors is an integer number (318315087).

Almost surely, 2^636630173 is an apocalyptic number.

It is an amenable number.

636630173 is a deficient number, since it is larger than the sum of its proper divisors (1).

636630173 is an equidigital number, since it uses as much as digits as its factorization.

636630173 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 35.

The square root of 636630173 is about 25231.5313249117. The cubic root of 636630173 is about 860.2586985381.

The spelling of 636630173 in words is "six hundred thirty-six million, six hundred thirty thousand, one hundred seventy-three".