71666 has 8 divisors (see below), whose sum is σ = 122880. Its totient is φ = 30708.

The previous prime is 71663. The next prime is 71671. The reversal of 71666 is 66617.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 71666.

It is not an unprimeable number, because it can be changed into a prime (71663) 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, 2546 + ... + 2573.

It is an arithmetic number, because the mean of its divisors is an integer number (15360).

2⁷¹⁶⁶⁶ is an apocalyptic number.

71666 is a deficient number, since it is larger than the sum of its proper divisors (51214).

71666 is a wasteful number, since it uses less digits than its factorization.

71666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5128.

The product of its digits is 1512, while the sum is 26.

The square root of 71666 is about 267.7050615883. The cubic root of 71666 is about 41.5372482147.

It can be divided in two parts, 71 and 666, that added together give a palindrome (737).

The spelling of 71666 in words is "seventy-one thousand, six hundred sixty-six".