636143341621 has 2 divisors, whose sum is σ = 636143341622. Its totient is φ = 636143341620.

The previous prime is 636143341597. The next prime is 636143341637. The reversal of 636143341621 is 126143341636.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 569550958596 + 66592383025 = 754686^2 + 258055^2 .

It is a cyclic number.

It is not a de Polignac number, because 636143341621 - 2²⁵ = 636109787189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (636143341651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318071670810 + 318071670811.

It is an arithmetic number, because the mean of its divisors is an integer number (318071670811).

Almost surely, 2^636143341621 is an apocalyptic number.

It is an amenable number.

636143341621 is a deficient number, since it is larger than the sum of its proper divisors (1).

636143341621 is an equidigital number, since it uses as much as digits as its factorization.

636143341621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 40.

The spelling of 636143341621 in words is "six hundred thirty-six billion, one hundred forty-three million, three hundred forty-one thousand, six hundred twenty-one".