66393539 has 2 divisors, whose sum is σ = 66393540. Its totient is φ = 66393538.

The previous prime is 66393533. The next prime is 66393541. The reversal of 66393539 is 93539366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66393539 - 2²⁰ = 65344963 is a prime.

Together with 66393541, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66393539.

It is not a weakly prime, because it can be changed into another prime (66393533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33196769 + 33196770.

It is an arithmetic number, because the mean of its divisors is an integer number (33196770).

Almost surely, 2^66393539 is an apocalyptic number.

66393539 is a deficient number, since it is larger than the sum of its proper divisors (1).

66393539 is an equidigital number, since it uses as much as digits as its factorization.

66393539 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 393660, while the sum is 44.

The square root of 66393539 is about 8148.2230578206. The cubic root of 66393539 is about 404.9256358918.

The spelling of 66393539 in words is "sixty-six million, three hundred ninety-three thousand, five hundred thirty-nine".