66866247 has 24 divisors (see below), whose sum is σ = 112953984. Its totient is φ = 37319184.

The previous prime is 66866243. The next prime is 66866249. The reversal of 66866247 is 74266866.

It is not a de Polignac number, because 66866247 - 2² = 66866243 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66866243) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9633 + ... + 15050.

It is an arithmetic number, because the mean of its divisors is an integer number (4706416).

Almost surely, 2^66866247 is an apocalyptic number.

66866247 is a deficient number, since it is larger than the sum of its proper divisors (46087737).

66866247 is a wasteful number, since it uses less digits than its factorization.

66866247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24739 (or 24736 counting only the distinct ones).

The product of its digits is 580608, while the sum is 45.

The square root of 66866247 is about 8177.1784253494. The cubic root of 66866247 is about 405.8843592287.

The spelling of 66866247 in words is "sixty-six million, eight hundred sixty-six thousand, two hundred forty-seven".