645731630360417 has 2 divisors, whose sum is σ = 645731630360418. Its totient is φ = 645731630360416.

The previous prime is 645731630360291. The next prime is 645731630360437. The reversal of 645731630360417 is 714063036137546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 625304837161216 + 20426793199201 = 25006096^2 + 4519601^2 .

It is a cyclic number.

It is not a de Polignac number, because 645731630360417 - 2⁴² = 641333583849313 is a prime.

It is not a weakly prime, because it can be changed into another prime (645731630360437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322865815180208 + 322865815180209.

It is an arithmetic number, because the mean of its divisors is an integer number (322865815180209).

Almost surely, 2^{645731630360417} is an apocalyptic number.

It is an amenable number.

645731630360417 is a deficient number, since it is larger than the sum of its proper divisors (1).

645731630360417 is an equidigital number, since it uses as much as digits as its factorization.

645731630360417 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22861440, while the sum is 56.

The spelling of 645731630360417 in words is "six hundred forty-five trillion, seven hundred thirty-one billion, six hundred thirty million, three hundred sixty thousand, four hundred seventeen".