646255206089 has 2 divisors, whose sum is σ = 646255206090. Its totient is φ = 646255206088.

The previous prime is 646255206053. The next prime is 646255206133. The reversal of 646255206089 is 980602552646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 604557566089 + 41697640000 = 777533^2 + 204200^2 .

It is a cyclic number.

It is not a de Polignac number, because 646255206089 - 2²⁰ = 646254157513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 646255206089.

It is not a weakly prime, because it can be changed into another prime (646255206889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323127603044 + 323127603045.

It is an arithmetic number, because the mean of its divisors is an integer number (323127603045).

Almost surely, 2^646255206089 is an apocalyptic number.

It is an amenable number.

646255206089 is a deficient number, since it is larger than the sum of its proper divisors (1).

646255206089 is an equidigital number, since it uses as much as digits as its factorization.

646255206089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6220800, while the sum is 53.

The spelling of 646255206089 in words is "six hundred forty-six billion, two hundred fifty-five million, two hundred six thousand, eighty-nine".