19699 has 2 divisors, whose sum is σ = 19700. Its totient is φ = 19698.

The previous prime is 19697. The next prime is 19709. The reversal of 19699 is 99691.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19699 - 2¹ = 19697 is a prime.

Together with 19697, it forms a pair of twin primes.

It is a plaindrome in base 5 and base 11.

It is a zygodrome in base 5.

It is not a weakly prime, because it can be changed into another prime (19697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9849 + 9850.

It is an arithmetic number, because the mean of its divisors is an integer number (9850).

2¹⁹⁶⁹⁹ is an apocalyptic number.

19699 is a deficient number, since it is larger than the sum of its proper divisors (1).

19699 is an equidigital number, since it uses as much as digits as its factorization.

19699 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4374, while the sum is 34.

The square root of 19699 is about 140.3531260785. The cubic root of 19699 is about 27.0073139765.

The spelling of 19699 in words is "nineteen thousand, six hundred ninety-nine".