646843513117 has 2 divisors, whose sum is σ = 646843513118. Its totient is φ = 646843513116.

The previous prime is 646843513081. The next prime is 646843513153. The reversal of 646843513117 is 711315348646.

It is a happy number.

646843513117 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (646843513081) and next prime (646843513153).

It can be written as a sum of positive squares in only one way, i.e., 534099334041 + 112744179076 = 730821^2 + 335774^2 .

It is a cyclic number.

It is not a de Polignac number, because 646843513117 - 2³⁹ = 97087699229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646843513187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323421756558 + 323421756559.

It is an arithmetic number, because the mean of its divisors is an integer number (323421756559).

Almost surely, 2^646843513117 is an apocalyptic number.

It is an amenable number.

646843513117 is a deficient number, since it is larger than the sum of its proper divisors (1).

646843513117 is an equidigital number, since it uses as much as digits as its factorization.

646843513117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1451520, while the sum is 49.

The spelling of 646843513117 in words is "six hundred forty-six billion, eight hundred forty-three million, five hundred thirteen thousand, one hundred seventeen".