4491 has 6 divisors (see below), whose sum is σ = 6500. Its totient is φ = 2988.

The previous prime is 4483. The next prime is 4493. The reversal of 4491 is 1944.

4491 = T₃ + T₄ + ... + T₂₉.

It is not a de Polignac number, because 4491 - 2³ = 4483 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 4491.

It is not an unprimeable number, because it can be changed into a prime (4493) 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, 241 + ... + 258.

2⁴⁴⁹¹ is an apocalyptic number.

4491 is a deficient number, since it is larger than the sum of its proper divisors (2009).

4491 is a wasteful number, since it uses less digits than its factorization.

4491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 505 (or 502 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 4491 is about 67.0149237111. The cubic root of 4491 is about 16.4986224745.

It can be divided in two parts, 44 and 91, that multiplied together give a palindrome (4004).

The spelling of 4491 in words is "four thousand, four hundred ninety-one".