6644622664549 has 2 divisors, whose sum is σ = 6644622664550. Its totient is φ = 6644622664548.

The previous prime is 6644622664541. The next prime is 6644622664609. The reversal of 6644622664549 is 9454662264466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6179485024449 + 465137640100 = 2485857^2 + 682010^2 .

It is a cyclic number.

It is not a de Polignac number, because 6644622664549 - 2³ = 6644622664541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6644622664541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3322311332274 + 3322311332275.

It is an arithmetic number, because the mean of its divisors is an integer number (3322311332275).

Almost surely, 2^{6644622664549} is an apocalyptic number.

It is an amenable number.

6644622664549 is a deficient number, since it is larger than the sum of its proper divisors (1).

6644622664549 is an equidigital number, since it uses as much as digits as its factorization.

6644622664549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 358318080, while the sum is 64.

The spelling of 6644622664549 in words is "six trillion, six hundred forty-four billion, six hundred twenty-two million, six hundred sixty-four thousand, five hundred forty-nine".