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2187 = 37

2187 has 8 divisors (see below), whose sum is σ = 3280. Its totient is φ = 1458.

The previous prime is 2179. The next prime is 2203. The reversal of 2187 is 7812.

It is a perfect power (a 7-th power), and thus also a powerful number.

It is an ABA number since it can be written as A⋅BA, here for A=3, B=9.

It is not a de Polignac number, because 2187 - 23 = 2179 is a prime.

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

It is a Duffinian number.

2187 is a lucky number.

It is a plaindrome in base 15 and base 16.

It is a nialpdrome in base 3, base 5, base 9 and base 13.

It is not an unprimeable number, because it can be changed into a prime (2137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 728 + 729 + 730.

It is an arithmetic number, because the mean of its divisors is an integer number (410).

2187 is a Friedman number, since it can be written as (8+1)^(7/2), using all its digits and the basic arithmetic operations.

It is a vampire number, since it can be written as 2781 (with its own digits).

22187 is an apocalyptic number.

2187 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

2187 is a deficient number, since it is larger than the sum of its proper divisors (1093).

2187 is an frugal number, since it uses more digits than its factorization.

2187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21 (or 3 counting only the distinct ones).

The product of its digits is 112, while the sum is 18.

The square root of 2187 is about 46.7653718044. The cubic root of 2187 is about 12.9802461328.

Adding to 2187 its reverse (7812), we get a palindrome (9999).

Subtracting 2187 from its reverse (7812), we obtain a square (5625 = 752).

It can be divided in two parts, 218 and 7, that added together give a square (225 = 152).

The spelling of 2187 in words is "two thousand, one hundred eighty-seven".

Divisors: 1 3 9 27 81 243 729 2187