66881189 has 2 divisors, whose sum is σ = 66881190. Its totient is φ = 66881188.

The previous prime is 66881149. The next prime is 66881231. The reversal of 66881189 is 98118866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59136100 + 7745089 = 7690^2 + 2783^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66881189 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 (66881149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33440594 + 33440595.

It is an arithmetic number, because the mean of its divisors is an integer number (33440595).

Almost surely, 2^66881189 is an apocalyptic number.

It is an amenable number.

66881189 is a deficient number, since it is larger than the sum of its proper divisors (1).

66881189 is an equidigital number, since it uses as much as digits as its factorization.

66881189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 165888, while the sum is 47.

The square root of 66881189 is about 8178.0920146450. The cubic root of 66881189 is about 405.9145900885.

The spelling of 66881189 in words is "sixty-six million, eight hundred eighty-one thousand, one hundred eighty-nine".