66489191 has 2 divisors, whose sum is σ = 66489192. Its totient is φ = 66489190.

The previous prime is 66489187. The next prime is 66489197. The reversal of 66489191 is 19198466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66489191 - 2² = 66489187 is a prime.

It is a Sophie Germain 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 (66489197) 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, 33244595 + 33244596.

It is an arithmetic number, because the mean of its divisors is an integer number (33244596).

Almost surely, 2^66489191 is an apocalyptic number.

66489191 is a deficient number, since it is larger than the sum of its proper divisors (1).

66489191 is an equidigital number, since it uses as much as digits as its factorization.

66489191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 44.

The square root of 66489191 is about 8154.0904459050. The cubic root of 66489191 is about 405.1199989891.

The spelling of 66489191 in words is "sixty-six million, four hundred eighty-nine thousand, one hundred ninety-one".