636142161 has 4 divisors (see below), whose sum is σ = 848189552. Its totient is φ = 424094772.

The previous prime is 636142151. The next prime is 636142187. The reversal of 636142161 is 161241636.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 636142161 - 2¹⁰ = 636141137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (636142151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106023691 + ... + 106023696.

It is an arithmetic number, because the mean of its divisors is an integer number (212047388).

Almost surely, 2^636142161 is an apocalyptic number.

It is an amenable number.

636142161 is a deficient number, since it is larger than the sum of its proper divisors (212047391).

636142161 is a wasteful number, since it uses less digits than its factorization.

636142161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212047390.

The product of its digits is 5184, while the sum is 30.

The square root of 636142161 is about 25221.8587935148. The cubic root of 636142161 is about 860.0388304984.

Adding to 636142161 its reverse (161241636), we get a palindrome (797383797).

The spelling of 636142161 in words is "six hundred thirty-six million, one hundred forty-two thousand, one hundred sixty-one".