66966239 has 4 divisors (see below), whose sum is σ = 68101320. Its totient is φ = 65831160.

The previous prime is 66966223. The next prime is 66966253. The reversal of 66966239 is 93266966.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66966239 - 2⁴ = 66966223 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66966193 and 66966202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66966209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 567452 + ... + 567569.

It is an arithmetic number, because the mean of its divisors is an integer number (17025330).

Almost surely, 2^66966239 is an apocalyptic number.

66966239 is a deficient number, since it is larger than the sum of its proper divisors (1135081).

66966239 is a wasteful number, since it uses less digits than its factorization.

66966239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1135080.

The product of its digits is 629856, while the sum is 47.

The square root of 66966239 is about 8183.2902307079. The cubic root of 66966239 is about 406.0865787194.

The spelling of 66966239 in words is "sixty-six million, nine hundred sixty-six thousand, two hundred thirty-nine".