66855193 has 2 divisors, whose sum is σ = 66855194. Its totient is φ = 66855192.

The previous prime is 66855163. The next prime is 66855199. The reversal of 66855193 is 39155866.

66855193 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60964864 + 5890329 = 7808^2 + 2427^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66855193 is a prime.

It is not a weakly prime, because it can be changed into another prime (66855199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33427596 + 33427597.

It is an arithmetic number, because the mean of its divisors is an integer number (33427597).

Almost surely, 2^66855193 is an apocalyptic number.

It is an amenable number.

66855193 is a deficient number, since it is larger than the sum of its proper divisors (1).

66855193 is an equidigital number, since it uses as much as digits as its factorization.

66855193 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 194400, while the sum is 43.

The square root of 66855193 is about 8176.5024918971. The cubic root of 66855193 is about 405.8619917256.

The spelling of 66855193 in words is "sixty-six million, eight hundred fifty-five thousand, one hundred ninety-three".