66247 has 4 divisors (see below), whose sum is σ = 68416. Its totient is φ = 64080.

The previous prime is 66239. The next prime is 66271. The reversal of 66247 is 74266.

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 66247 - 2³ = 66239 is a prime.

It is a Duffinian number.

66247 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1038 + ... + 1099.

It is an arithmetic number, because the mean of its divisors is an integer number (17104).

2⁶⁶²⁴⁷ is an apocalyptic number.

66247 is a deficient number, since it is larger than the sum of its proper divisors (2169).

66247 is a wasteful number, since it uses less digits than its factorization.

66247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2168.

The product of its digits is 2016, while the sum is 25.

The square root of 66247 is about 257.3849257435. The cubic root of 66247 is about 40.4627508959.

It can be divided in two parts, 66 and 247, that added together give a palindrome (313).

The spelling of 66247 in words is "sixty-six thousand, two hundred forty-seven".