636851471828101 has 4 divisors (see below), whose sum is σ = 637121667618252. Its totient is φ = 636581276037952.

The previous prime is 636851471828083. The next prime is 636851471828161. The reversal of 636851471828101 is 101828174158636.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 207956732697025 + 428894739131076 = 14420705^2 + 20709774^2 .

It is a cyclic number.

It is not a de Polignac number, because 636851471828101 - 2⁵ = 636851471828069 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 636851471828101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636851471828161) 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 3 ways as a sum of consecutive naturals, for example, 135097891540 + ... + 135097896253.

It is an arithmetic number, because the mean of its divisors is an integer number (159280416904563).

Almost surely, 2^{636851471828101} is an apocalyptic number.

It is an amenable number.

636851471828101 is a deficient number, since it is larger than the sum of its proper divisors (270195790151).

636851471828101 is a wasteful number, since it uses less digits than its factorization.

636851471828101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270195790150.

The product of its (nonzero) digits is 15482880, while the sum is 61.

The spelling of 636851471828101 in words is "six hundred thirty-six trillion, eight hundred fifty-one billion, four hundred seventy-one million, eight hundred twenty-eight thousand, one hundred one".