75666 has 8 divisors (see below), whose sum is σ = 151344. Its totient is φ = 25220.

The previous prime is 75659. The next prime is 75679. The reversal of 75666 is 66657.

75666 = T₄₆ + T₄₇ + ... + T₈₁.

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

75666 is an admirable number.

It is an unprimeable number.

75666 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6300 + ... + 6311.

It is an arithmetic number, because the mean of its divisors is an integer number (18918).

2⁷⁵⁶⁶⁶ is an apocalyptic number.

75666 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75672).

75666 is a wasteful number, since it uses less digits than its factorization.

75666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12616.

The product of its digits is 7560, while the sum is 30.

The square root of 75666 is about 275.0745353536. The cubic root of 75666 is about 42.2960936207.

Subtracting from 75666 its reverse (66657), we obtain a palindrome (9009).

It can be divided in two parts, 75 and 666, that added together give a triangular number (741 = T₃₈).

The spelling of 75666 in words is "seventy-five thousand, six hundred sixty-six".