66799559 has 2 divisors, whose sum is σ = 66799560. Its totient is φ = 66799558.

The previous prime is 66799547. The next prime is 66799561. The reversal of 66799559 is 95599766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66799559 - 2⁸ = 66799303 is a prime.

Together with 66799561, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66799589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33399779 + 33399780.

It is an arithmetic number, because the mean of its divisors is an integer number (33399780).

Almost surely, 2^66799559 is an apocalyptic number.

66799559 is a deficient number, since it is larger than the sum of its proper divisors (1).

66799559 is an equidigital number, since it uses as much as digits as its factorization.

66799559 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4592700, while the sum is 56.

The square root of 66799559 is about 8173.0997179773. The cubic root of 66799559 is about 405.7493802180.

The spelling of 66799559 in words is "sixty-six million, seven hundred ninety-nine thousand, five hundred fifty-nine".