636039161 has 2 divisors, whose sum is σ = 636039162. Its totient is φ = 636039160.

The previous prime is 636039143. The next prime is 636039163. The reversal of 636039161 is 161930636.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 587820025 + 48219136 = 24245^2 + 6944^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-636039161 is a prime.

Together with 636039163, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (636039163) 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, 318019580 + 318019581.

It is an arithmetic number, because the mean of its divisors is an integer number (318019581).

Almost surely, 2^636039161 is an apocalyptic number.

It is an amenable number.

636039161 is a deficient number, since it is larger than the sum of its proper divisors (1).

636039161 is an equidigital number, since it uses as much as digits as its factorization.

636039161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 35.

The square root of 636039161 is about 25219.8168312143. The cubic root of 636039161 is about 859.9924106956.

Adding to 636039161 its reverse (161930636), we get a palindrome (797969797).

The spelling of 636039161 in words is "six hundred thirty-six million, thirty-nine thousand, one hundred sixty-one".