66889189 has 2 divisors, whose sum is σ = 66889190. Its totient is φ = 66889188.

The previous prime is 66889157. The next prime is 66889201. The reversal of 66889189 is 98198866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66830625 + 58564 = 8175^2 + 242^2 .

It is a cyclic number.

It is not a de Polignac number, because 66889189 - 2⁵ = 66889157 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66881189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33444594 + 33444595.

It is an arithmetic number, because the mean of its divisors is an integer number (33444595).

Almost surely, 2^66889189 is an apocalyptic number.

It is an amenable number.

66889189 is a deficient number, since it is larger than the sum of its proper divisors (1).

66889189 is an equidigital number, since it uses as much as digits as its factorization.

66889189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1492992, while the sum is 55.

The square root of 66889189 is about 8178.5811116599. The cubic root of 66889189 is about 405.9307739478.

The spelling of 66889189 in words is "sixty-six million, eight hundred eighty-nine thousand, one hundred eighty-nine".