636677221213 has 4 divisors (see below), whose sum is σ = 694556968608. Its totient is φ = 578797473820.

The previous prime is 636677221207. The next prime is 636677221259. The reversal of 636677221213 is 312122776636.

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 a cyclic number.

It is not a de Polignac number, because 636677221213 - 2⁵ = 636677221181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636677221273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28939873681 + ... + 28939873702.

It is an arithmetic number, because the mean of its divisors is an integer number (173639242152).

Almost surely, 2^636677221213 is an apocalyptic number.

It is an amenable number.

636677221213 is a deficient number, since it is larger than the sum of its proper divisors (57879747395).

636677221213 is a wasteful number, since it uses less digits than its factorization.

636677221213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57879747394.

The product of its digits is 762048, while the sum is 46.

Adding to 636677221213 its reverse (312122776636), we get a palindrome (948799997849).

The spelling of 636677221213 in words is "six hundred thirty-six billion, six hundred seventy-seven million, two hundred twenty-one thousand, two hundred thirteen".