66666249 has 12 divisors (see below), whose sum is σ = 103703236. Its totient is φ = 41025312.

The previous prime is 66666247. The next prime is 66666263. The reversal of 66666249 is 94266666.

It can be written as a sum of positive squares in 2 ways, for example, as 7868025 + 58798224 = 2805^2 + 7668^2 .

It is not a de Polignac number, because 66666249 - 2¹ = 66666247 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66666247) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 284782 + ... + 285015.

Almost surely, 2^66666249 is an apocalyptic number.

It is an amenable number.

66666249 is a deficient number, since it is larger than the sum of its proper divisors (37036987).

66666249 is a wasteful number, since it uses less digits than its factorization.

66666249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569816 (or 569813 counting only the distinct ones).

The product of its digits is 559872, while the sum is 45.

The square root of 66666249 is about 8164.9402324818. The cubic root of 66666249 is about 405.4792862588.

The spelling of 66666249 in words is "sixty-six million, six hundred sixty-six thousand, two hundred forty-nine".