13491 has 6 divisors (see below), whose sum is σ = 19500. Its totient is φ = 8988.

The previous prime is 13487. The next prime is 13499. The reversal of 13491 is 19431.

It is not a de Polignac number, because 13491 - 2² = 13487 is a prime.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (13499) 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, 741 + ... + 758.

It is an arithmetic number, because the mean of its divisors is an integer number (3250).

2¹³⁴⁹¹ is an apocalyptic number.

13491 is a deficient number, since it is larger than the sum of its proper divisors (6009).

13491 is a wasteful number, since it uses less digits than its factorization.

13491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1505 (or 1502 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 13491 is about 116.1507640956. The cubic root of 13491 is about 23.8057232664.

It can be divided in two parts, 134 and 91, that added together give a square (225 = 15²).

The spelling of 13491 in words is "thirteen thousand, four hundred ninety-one".