5491 has 6 divisors (see below), whose sum is σ = 6140. Its totient is φ = 4896.

The previous prime is 5483. The next prime is 5501. The reversal of 5491 is 1945.

5491 = T₅₉ + T₆₀ + T₆₁.

It is not a de Polignac number, because 5491 - 2³ = 5483 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

Its product of digits (180) is a multiple of the sum of its prime divisors (36).

5491 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (5431) 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, 280 + ... + 298.

2⁵⁴⁹¹ is an apocalyptic number.

5491 is the 61-st centered triangular number.

5491 is a deficient number, since it is larger than the sum of its proper divisors (649).

5491 is a wasteful number, since it uses less digits than its factorization.

5491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53 (or 36 counting only the distinct ones).

The product of its digits is 180, while the sum is 19.

The square root of 5491 is about 74.1012820402. The cubic root of 5491 is about 17.6421081974.

Multiplying 5491 by its sum of digits (19), we get a square (104329 = 323²).

5491 divided by its sum of digits (19) gives a square (289 = 17²).

Adding to 5491 its product of digits (180), we get a triangular number (5671 = T₁₀₆).

It can be divided in two parts, 5 and 491, that added together give a triangular number (496 = T₃₁).

The spelling of 5491 in words is "five thousand, four hundred ninety-one".