1644081967573 has 2 divisors, whose sum is σ = 1644081967574. Its totient is φ = 1644081967572.

The previous prime is 1644081967529. The next prime is 1644081967607. The reversal of 1644081967573 is 3757691804461.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1592787871249 + 51294096324 = 1262057^2 + 226482^2 .

It is a cyclic number.

It is not a de Polignac number, because 1644081967573 - 2²⁵ = 1644048413141 is a prime.

It is a super-3 number, since 3×1644081967573³ (a number of 38 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1644081967873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822040983786 + 822040983787.

It is an arithmetic number, because the mean of its divisors is an integer number (822040983787).

Almost surely, 2^{1644081967573} is an apocalyptic number.

It is an amenable number.

1644081967573 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644081967573 is an equidigital number, since it uses as much as digits as its factorization.

1644081967573 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30481920, while the sum is 61.

The spelling of 1644081967573 in words is "one trillion, six hundred forty-four billion, eighty-one million, nine hundred sixty-seven thousand, five hundred seventy-three".