636234432661 has 2 divisors, whose sum is σ = 636234432662. Its totient is φ = 636234432660.

The previous prime is 636234432599. The next prime is 636234432683. The reversal of 636234432661 is 166234432636.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 557389162225 + 78845270436 = 746585^2 + 280794^2 .

It is a cyclic number.

It is not a de Polignac number, because 636234432661 - 2²¹ = 636232335509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (636234438661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318117216330 + 318117216331.

It is an arithmetic number, because the mean of its divisors is an integer number (318117216331).

Almost surely, 2^636234432661 is an apocalyptic number.

It is an amenable number.

636234432661 is a deficient number, since it is larger than the sum of its proper divisors (1).

636234432661 is an equidigital number, since it uses as much as digits as its factorization.

636234432661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 46.

The spelling of 636234432661 in words is "six hundred thirty-six billion, two hundred thirty-four million, four hundred thirty-two thousand, six hundred sixty-one".