66644244239 has 2 divisors, whose sum is σ = 66644244240. Its totient is φ = 66644244238.

The previous prime is 66644244209. The next prime is 66644244319. The reversal of 66644244239 is 93244244666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66644244239 - 2²⁸ = 66375808783 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66644244209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33322122119 + 33322122120.

It is an arithmetic number, because the mean of its divisors is an integer number (33322122120).

Almost surely, 2^66644244239 is an apocalyptic number.

66644244239 is a deficient number, since it is larger than the sum of its proper divisors (1).

66644244239 is an equidigital number, since it uses as much as digits as its factorization.

66644244239 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5971968, while the sum is 50.

The spelling of 66644244239 in words is "sixty-six billion, six hundred forty-four million, two hundred forty-four thousand, two hundred thirty-nine".