66445289 has 2 divisors, whose sum is σ = 66445290. Its totient is φ = 66445288.

The previous prime is 66445259. The next prime is 66445361. The reversal of 66445289 is 98254466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52998400 + 13446889 = 7280^2 + 3667^2 .

It is a cyclic number.

It is not a de Polignac number, because 66445289 - 2²⁰ = 65396713 is a prime.

It is not a weakly prime, because it can be changed into another prime (66445219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33222644 + 33222645.

It is an arithmetic number, because the mean of its divisors is an integer number (33222645).

Almost surely, 2^66445289 is an apocalyptic number.

It is an amenable number.

66445289 is a deficient number, since it is larger than the sum of its proper divisors (1).

66445289 is an equidigital number, since it uses as much as digits as its factorization.

66445289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 414720, while the sum is 44.

The square root of 66445289 is about 8151.3979782612. The cubic root of 66445289 is about 405.0308140961.

The spelling of 66445289 in words is "sixty-six million, four hundred forty-five thousand, two hundred eighty-nine".