6644644333081 has 2 divisors, whose sum is σ = 6644644333082. Its totient is φ = 6644644333080.

The previous prime is 6644644333049. The next prime is 6644644333087. The reversal of 6644644333081 is 1803334464466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4461638083081 + 2183006250000 = 2112259^2 + 1477500^2 .

It is a cyclic number.

It is not a de Polignac number, because 6644644333081 - 2⁵ = 6644644333049 is a prime.

It is a super-2 number, since 2×6644644333081² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6644644333087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3322322166540 + 3322322166541.

It is an arithmetic number, because the mean of its divisors is an integer number (3322322166541).

Almost surely, 2^{6644644333081} is an apocalyptic number.

It is an amenable number.

6644644333081 is a deficient number, since it is larger than the sum of its proper divisors (1).

6644644333081 is an equidigital number, since it uses as much as digits as its factorization.

6644644333081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11943936, while the sum is 52.

The spelling of 6644644333081 in words is "six trillion, six hundred forty-four billion, six hundred forty-four million, three hundred thirty-three thousand, eighty-one".