644466525133 has 2 divisors, whose sum is σ = 644466525134. Its totient is φ = 644466525132.

The previous prime is 644466525127. The next prime is 644466525173. The reversal of 644466525133 is 331525664446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 410731019689 + 233735505444 = 640883^2 + 483462^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-644466525133 is a prime.

It is a super-4 number, since 4×644466525133⁴ (a number of 48 digits) contains 4444 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644466525113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322233262566 + 322233262567.

It is an arithmetic number, because the mean of its divisors is an integer number (322233262567).

Almost surely, 2^644466525133 is an apocalyptic number.

It is an amenable number.

644466525133 is a deficient number, since it is larger than the sum of its proper divisors (1).

644466525133 is an equidigital number, since it uses as much as digits as its factorization.

644466525133 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6220800, while the sum is 49.

The spelling of 644466525133 in words is "six hundred forty-four billion, four hundred sixty-six million, five hundred twenty-five thousand, one hundred thirty-three".