66943589 has 2 divisors, whose sum is σ = 66943590. Its totient is φ = 66943588.

The previous prime is 66943579. The next prime is 66943607. The reversal of 66943589 is 98534966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66552964 + 390625 = 8158^2 + 625^2 .

It is a cyclic number.

It is not a de Polignac number, because 66943589 - 2⁸ = 66943333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66943559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33471794 + 33471795.

It is an arithmetic number, because the mean of its divisors is an integer number (33471795).

Almost surely, 2^66943589 is an apocalyptic number.

It is an amenable number.

66943589 is a deficient number, since it is larger than the sum of its proper divisors (1).

66943589 is an equidigital number, since it uses as much as digits as its factorization.

66943589 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1399680, while the sum is 50.

The square root of 66943589 is about 8181.9061959912. The cubic root of 66943589 is about 406.0407899840.

The spelling of 66943589 in words is "sixty-six million, nine hundred forty-three thousand, five hundred eighty-nine".