187 has 4 divisors (see below), whose sum is σ = 216. Its totient is φ = 160.

The previous prime is 181. The next prime is 191. The reversal of 187 is 781.

187 is nontrivially palindromic in base 16.

187 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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 781 = 11 ⋅71.

It is a cyclic number.

It is not a de Polignac number, because 187 - 2³ = 179 is a prime.

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

It is a Duffinian number.

187 is an undulating number in base 4.

Its product of digits (56) is a multiple of the sum of its prime divisors (28).

187 is a nontrivial repdigit in base 16.

It is a plaindrome in base 5, base 7, base 9, base 12, base 13 and base 16.

It is a nialpdrome in base 6, base 14, base 15 and base 16.

It is a zygodrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 187.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3 + ... + 19.

It is an arithmetic number, because the mean of its divisors is an integer number (54).

187 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

187 is a deficient number, since it is larger than the sum of its proper divisors (29).

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

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

The sum of its prime factors is 28.

The product of its digits is 56, while the sum is 16.

The square root of 187 is about 13.6747943312. The cubic root of 187 is about 5.7184790649.

Subtracting from 187 its sum of digits (16), we obtain a palindrome (171).

Multiplying 187 by its sum of digits (16), we get a palindrome (2992).

Adding to 187 its product of digits (56), we get a 5-th power (243 = 3⁵).

Subtracting from 187 its product of digits (56), we obtain a palindrome (131).

It can be divided in two parts, 18 and 7, that added together give a square (25 = 5²).

The spelling of 187 in words is "one hundred eighty-seven", and thus it is an aban number.