17491 has 2 divisors, whose sum is σ = 17492.
Its totient is φ = 17490.
The previous prime is 17489. The next prime is 17497. The reversal of 17491 is 19471.
It is a weak prime.
It is an emirp because it is prime and its reverse (19471) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 17491 - 21 = 17489 is a prime.
It is a super-3 number, since 3×174913 = 16053331505313, which contains 333 as substring.
Together with 17489, it forms a pair of twin primes.
It is not a weakly prime, because it can be changed into another prime (17497) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8745 + 8746.
It is an arithmetic number, because the mean of its divisors is an integer number (8746).
217491 is an apocalyptic number.
17491 is a deficient number, since it is larger than the sum of its proper divisors (1).
17491 is an equidigital number, since it uses as much as digits as its factorization.
17491 is an evil number, because the sum of its binary digits is even.
The product of its digits is 252, while the sum is 22.
The square root of 17491 is about 132.2535443759.
The cubic root of 17491 is about 25.9580190368.
The spelling of 17491 in words is "seventeen thousand, four hundred ninety-one".