66866243 has 2 divisors, whose sum is σ = 66866244. Its totient is φ = 66866242.

The previous prime is 66866227. The next prime is 66866249. The reversal of 66866243 is 34266866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66866243 - 2⁴ = 66866227 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66866243.

It is not a weakly prime, because it can be changed into another prime (66866249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33433121 + 33433122.

It is an arithmetic number, because the mean of its divisors is an integer number (33433122).

Almost surely, 2^66866243 is an apocalyptic number.

66866243 is a deficient number, since it is larger than the sum of its proper divisors (1).

66866243 is an equidigital number, since it uses as much as digits as its factorization.

66866243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 41.

The square root of 66866243 is about 8177.1781807663. The cubic root of 66866243 is about 405.8843511353.

The spelling of 66866243 in words is "sixty-six million, eight hundred sixty-six thousand, two hundred forty-three".