66967889 has 2 divisors, whose sum is σ = 66967890. Its totient is φ = 66967888.

The previous prime is 66967871. The next prime is 66967919. The reversal of 66967889 is 98876966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66961489 + 6400 = 8183^2 + 80^2 .

It is a cyclic number.

It is not a de Polignac number, because 66967889 - 2²⁰ = 65919313 is a prime.

It is not a weakly prime, because it can be changed into another prime (66967829) 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, 33483944 + 33483945.

It is an arithmetic number, because the mean of its divisors is an integer number (33483945).

Almost surely, 2^66967889 is an apocalyptic number.

It is an amenable number.

66967889 is a deficient number, since it is larger than the sum of its proper divisors (1).

66967889 is an equidigital number, since it uses as much as digits as its factorization.

66967889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 59.

The square root of 66967889 is about 8183.3910452819. The cubic root of 66967889 is about 406.0899139192.

The spelling of 66967889 in words is "sixty-six million, nine hundred sixty-seven thousand, eight hundred eighty-nine".