2169 has 6 divisors (see below), whose sum is σ = 3146. Its totient is φ = 1440.

The previous prime is 2161. The next prime is 2179. The reversal of 2169 is 9612.

Added to its reverse (9612) it gives a triangular number (11781 = T_{153}).

2169 is nontrivially palindromic in base 15.

2169 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 2025 + 144 = 45^2 + 12^2 .

It is not a de Polignac number, because 2169 - 2^{3} = 2161 is a prime.

It is a super-2 number, since 2×2169^{2} = 9409122, which contains 22 as substring.

It is a Leyland number of the form 11^{2} + 2^{11}.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

2169 is a nontrivial repdigit in base 15.

It is a plaindrome in base 15.

It is a nialpdrome in base 3 and base 15.

It is a zygodrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (2161) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 112 + ... + 129.

It is an amenable number.

2169 is a deficient number, since it is larger than the sum of its proper divisors (977).

2169 is a wasteful number, since it uses less digits than its factorization.

2169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247 (or 244 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 2169 is about 46.5725240888. The cubic root of 2169 is about 12.9445368846.

Adding to 2169 its sum of digits (18), we get a 7-th power (2187 = 3^{7}).

Adding to 2169 its reverse (9612), we get a triangular number (11781 = T_{153}).

It can be divided in two parts, 216 and 9, that added together give a square (225 = 15^{2}).

The spelling of 2169 in words is "two thousand, one hundred sixty-nine".

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