66390598849 has 2 divisors, whose sum is σ = 66390598850. Its totient is φ = 66390598848.

The previous prime is 66390598819. The next prime is 66390598943. The reversal of 66390598849 is 94889509366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41185861249 + 25204737600 = 202943^2 + 158760^2 .

It is a cyclic number.

It is not a de Polignac number, because 66390598849 - 2²⁹ = 65853727937 is a prime.

It is not a weakly prime, because it can be changed into another prime (66390598819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33195299424 + 33195299425.

It is an arithmetic number, because the mean of its divisors is an integer number (33195299425).

Almost surely, 2^66390598849 is an apocalyptic number.

It is an amenable number.

66390598849 is a deficient number, since it is larger than the sum of its proper divisors (1).

66390598849 is an equidigital number, since it uses as much as digits as its factorization.

66390598849 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 100776960, while the sum is 67.

The spelling of 66390598849 in words is "sixty-six billion, three hundred ninety million, five hundred ninety-eight thousand, eight hundred forty-nine".