1660 has 12 divisors (see below), whose sum is σ = 3528. Its totient is φ = 656.

The previous prime is 1657. The next prime is 1663. The reversal of 1660 is 661.

1660 = T₁₃ + T₁₄ + ... + T₂₂.

1660 is nontrivially palindromic in base 13 and base 14.

1660 is an esthetic number in base 13, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (1657) and next prime (1663).

It is an Ulam number.

1660 is an undulating number in base 13 and base 14.

It is a plaindrome in base 9, base 11 and base 16.

It is a nialpdrome in base 12.

It is a zygodrome in base 2 and base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 1660.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663) 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, 22 + ... + 61.

It is an arithmetic number, because the mean of its divisors is an integer number (294).

1660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1660 is an abundant number, since it is smaller than the sum of its proper divisors (1868).

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 (1764).

1660 is a wasteful number, since it uses less digits than its factorization.

1660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 1660 is about 40.7430975749. The cubic root of 1660 is about 11.8404814754.

Subtracting from 1660 its reverse (661), we obtain a palindrome (999).

The spelling of 1660 in words is "one thousand, six hundred sixty".