636245961121 has 8 divisors (see below), whose sum is σ = 637850911400. Its totient is φ = 634642594560.

The previous prime is 636245961083. The next prime is 636245961133. The reversal of 636245961121 is 121169542636.

It can be written as a sum of positive squares in 4 ways, for example, as 3926776896 + 632319184225 = 62664^2 + 795185^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-636245961121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (636245961151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 410635 + ... + 1200463.

It is an arithmetic number, because the mean of its divisors is an integer number (79731363925).

Almost surely, 2^636245961121 is an apocalyptic number.

It is an amenable number.

636245961121 is a deficient number, since it is larger than the sum of its proper divisors (1604950279).

636245961121 is a wasteful number, since it uses less digits than its factorization.

636245961121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791859.

The product of its digits is 466560, while the sum is 46.

The spelling of 636245961121 in words is "six hundred thirty-six billion, two hundred forty-five million, nine hundred sixty-one thousand, one hundred twenty-one".