1766 has 4 divisors (see below), whose sum is σ = 2652. Its totient is φ = 882.

The previous prime is 1759. The next prime is 1777. The reversal of 1766 is 6671.

1766 is nontrivially palindromic in base 16.

1766 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

1766 is an esthetic number in base 4, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6671 = 7 ⋅953.

1766 is an undulating number in base 16.

1766 is strictly pandigital in base 5.

It is a Curzon number.

It is a plaindrome in base 8 and base 11.

It is a congruent number.

It is an unprimeable number.

1766 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 as a sum of consecutive naturals, namely, 440 + ... + 443.

It is an arithmetic number, because the mean of its divisors is an integer number (663).

2¹⁷⁶⁶ is an apocalyptic number.

1766 is a deficient number, since it is larger than the sum of its proper divisors (886).

1766 is an equidigital number, since it uses as much as digits as its factorization.

1766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885.

The product of its digits is 252, while the sum is 20.

The square root of 1766 is about 42.0238027789. The cubic root of 1766 is about 12.0873259365.

It can be divided in two parts, 1 and 766, that added together give a palindrome (767).

The spelling of 1766 in words is "one thousand, seven hundred sixty-six".