646243330010909 has 2 divisors, whose sum is σ = 646243330010910. Its totient is φ = 646243330010908.

The previous prime is 646243330010893. The next prime is 646243330011007. The reversal of 646243330010909 is 909010033342646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 412986529084900 + 233256800926009 = 20322070^2 + 15272747^2 .

It is a cyclic number.

It is not a de Polignac number, because 646243330010909 - 2⁴ = 646243330010893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646243330010209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323121665005454 + 323121665005455.

It is an arithmetic number, because the mean of its divisors is an integer number (323121665005455).

Almost surely, 2^{646243330010909} is an apocalyptic number.

It is an amenable number.

646243330010909 is a deficient number, since it is larger than the sum of its proper divisors (1).

646243330010909 is an equidigital number, since it uses as much as digits as its factorization.

646243330010909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2519424, while the sum is 50.

The spelling of 646243330010909 in words is "six hundred forty-six trillion, two hundred forty-three billion, three hundred thirty million, ten thousand, nine hundred nine".