636406339217 has 4 divisors (see below), whose sum is σ = 694261460976. Its totient is φ = 578551217460.

The previous prime is 636406339211. The next prime is 636406339229. The reversal of 636406339217 is 712933604636.

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 a de Polignac number, because none of the positive numbers 2^k-636406339217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (636406339211) 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, 28927560863 + ... + 28927560884.

It is an arithmetic number, because the mean of its divisors is an integer number (173565365244).

Almost surely, 2^636406339217 is an apocalyptic number.

It is an amenable number.

636406339217 is a deficient number, since it is larger than the sum of its proper divisors (57855121759).

636406339217 is a wasteful number, since it uses less digits than its factorization.

636406339217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57855121758.

The product of its (nonzero) digits is 2939328, while the sum is 50.

The spelling of 636406339217 in words is "six hundred thirty-six billion, four hundred six million, three hundred thirty-nine thousand, two hundred seventeen".