644858552753 has 2 divisors, whose sum is σ = 644858552754. Its totient is φ = 644858552752.

The previous prime is 644858552729. The next prime is 644858552857. The reversal of 644858552753 is 357255858446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 339367997809 + 305490554944 = 582553^2 + 552712^2 .

It is a cyclic number.

It is not a de Polignac number, because 644858552753 - 2⁸ = 644858552497 is a prime.

It is not a weakly prime, because it can be changed into another prime (644858552353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322429276376 + 322429276377.

It is an arithmetic number, because the mean of its divisors is an integer number (322429276377).

Almost surely, 2^644858552753 is an apocalyptic number.

It is an amenable number.

644858552753 is a deficient number, since it is larger than the sum of its proper divisors (1).

644858552753 is an equidigital number, since it uses as much as digits as its factorization.

644858552753 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280000, while the sum is 62.

The spelling of 644858552753 in words is "six hundred forty-four billion, eight hundred fifty-eight million, five hundred fifty-two thousand, seven hundred fifty-three".