644241058493 has 2 divisors, whose sum is σ = 644241058494. Its totient is φ = 644241058492.

The previous prime is 644241058411. The next prime is 644241058507. The reversal of 644241058493 is 394850142446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 573167098084 + 71073960409 = 757078^2 + 266597^2 .

It is a cyclic number.

It is not a de Polignac number, because 644241058493 - 2¹⁶ = 644240992957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644241058403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322120529246 + 322120529247.

It is an arithmetic number, because the mean of its divisors is an integer number (322120529247).

Almost surely, 2^644241058493 is an apocalyptic number.

It is an amenable number.

644241058493 is a deficient number, since it is larger than the sum of its proper divisors (1).

644241058493 is an equidigital number, since it uses as much as digits as its factorization.

644241058493 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3317760, while the sum is 50.

The spelling of 644241058493 in words is "six hundred forty-four billion, two hundred forty-one million, fifty-eight thousand, four hundred ninety-three".