66996289 has 4 divisors (see below), whose sum is σ = 67030740. Its totient is φ = 66961840.

The previous prime is 66996277. The next prime is 66996311. The reversal of 66996289 is 98269966.

66996289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98269966 = 2 ⋅49134983.

It can be written as a sum of positive squares in 2 ways, for example, as 24850225 + 42146064 = 4985^2 + 6492^2 .

It is a cyclic number.

It is not a de Polignac number, because 66996289 - 2⁷ = 66996161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66996089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14122 + ... + 18259.

It is an arithmetic number, because the mean of its divisors is an integer number (16757685).

Almost surely, 2^66996289 is an apocalyptic number.

It is an amenable number.

66996289 is a deficient number, since it is larger than the sum of its proper divisors (34451).

66996289 is a wasteful number, since it uses less digits than its factorization.

66996289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34450.

The product of its digits is 2519424, while the sum is 55.

The square root of 66996289 is about 8185.1260833294. The cubic root of 66996289 is about 406.1473111972.

The spelling of 66996289 in words is "sixty-six million, nine hundred ninety-six thousand, two hundred eighty-nine".