66806245939 has 2 divisors, whose sum is σ = 66806245940. Its totient is φ = 66806245938.

The previous prime is 66806245931. The next prime is 66806246011. The reversal of 66806245939 is 93954260866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66806245939 - 2³ = 66806245931 is a prime.

It is not a weakly prime, because it can be changed into another prime (66806245931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33403122969 + 33403122970.

It is an arithmetic number, because the mean of its divisors is an integer number (33403122970).

Almost surely, 2^66806245939 is an apocalyptic number.

66806245939 is a deficient number, since it is larger than the sum of its proper divisors (1).

66806245939 is an equidigital number, since it uses as much as digits as its factorization.

66806245939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16796160, while the sum is 58.

The spelling of 66806245939 in words is "sixty-six billion, eight hundred six million, two hundred forty-five thousand, nine hundred thirty-nine".