4891 has 4 divisors (see below), whose sum is σ = 5032.
Its totient is φ = 4752.
The previous prime is 4889. The next prime is 4903. The reversal of 4891 is 1984.
Adding to 4891 its sum of digits (22), we get a cube (4913 = 173).
4891 = 262 + 272 + ... + 312.
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.
It is a cyclic number.
It is not a de Polignac number, because 4891 - 21 = 4889 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (4801) 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, 31 + ... + 103.
It is an arithmetic number, because the mean of its divisors is an integer number (1258).
4891 is a deficient number, since it is larger than the sum of its proper divisors (141).
4891 is an equidigital number, since it uses as much as digits as its factorization.
4891 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 140.
The product of its digits is 288, while the sum is 22.
The square root of 4891 is about 69.9356847396.
The cubic root of 4891 is about 16.9745871742.
The spelling of 4891 in words is "four thousand, eight hundred ninety-one".