1181 has 2 divisors, whose sum is σ = 1182.
Its totient is φ = 1180.
The previous prime is 1171. The next prime is 1187. The reversal of 1181 is 1811.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 1156 + 25 = 34^2 + 5^2
It is an emirp because it is prime and its reverse (1811) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 1181 - 26 = 1117 is a prime.
It is a super-2 number, since 2×11812 = 2789522, which contains 22 as substring.
It is a plaindrome in base 8 and base 16.
It is a nialpdrome in base 11.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1187) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 590 + 591.
It is an arithmetic number, because the mean of its divisors is an integer number (591).
It is an amenable number.
1181 is a deficient number, since it is larger than the sum of its proper divisors (1).
1181 is an equidigital number, since it uses as much as digits as its factorization.
1181 is an evil number, because the sum of its binary digits is even.
The product of its digits is 8, while the sum is 11.
The square root of 1181 is about 34.3656805549.
The cubic root of 1181 is about 10.5702022996.
Adding to 1181 its reverse (1811), we get a palindrome (2992).
Subtracting 1181 from its reverse (1811), we obtain a triangular number (630 = T35).
The spelling of 1181 in words is "one thousand, one hundred eighty-one".