636530644061 has 8 divisors (see below), whose sum is σ = 688568509440. Its totient is φ = 584931917232.

The previous prime is 636530644021. The next prime is 636530644063. The reversal of 636530644061 is 160446035636.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-636530644061 is a prime.

It is a super-2 number, since 2×636530644061² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636530644063) 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 in 7 ways as a sum of consecutive naturals, for example, 109781621 + ... + 109787418.

It is an arithmetic number, because the mean of its divisors is an integer number (86071063680).

Almost surely, 2^636530644061 is an apocalyptic number.

It is an amenable number.

636530644061 is a deficient number, since it is larger than the sum of its proper divisors (52037865379).

636530644061 is a wasteful number, since it uses less digits than its factorization.

636530644061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219569275.

The product of its (nonzero) digits is 933120, while the sum is 44.

Adding to 636530644061 its reverse (160446035636), we get a palindrome (796976679697).

The spelling of 636530644061 in words is "six hundred thirty-six billion, five hundred thirty million, six hundred forty-four thousand, sixty-one".