19717 has 2 divisors, whose sum is σ = 19718.
Its totient is φ = 19716.
The previous prime is 19709. The next prime is 19727. The reversal of 19717 is 71791.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 12321 + 7396 = 111^2 + 86^2
It is a cyclic number.
It is not a de Polignac number, because 19717 - 23 = 19709 is a prime.
It is a junction number, because it is equal to n+sod(n) for n = 19691 and 19700.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (19727) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9858 + 9859.
It is an arithmetic number, because the mean of its divisors is an integer number (9859).
219717 is an apocalyptic number.
It is an amenable number.
19717 is a deficient number, since it is larger than the sum of its proper divisors (1).
19717 is an equidigital number, since it uses as much as digits as its factorization.
19717 is an evil number, because the sum of its binary digits is even.
The product of its digits is 441, while the sum is 25.
The square root of 19717 is about 140.4172354093.
The cubic root of 19717 is about 27.0155374677.
The spelling of 19717 in words is "nineteen thousand, seven hundred seventeen".