19969 has 4 divisors (see below), whose sum is σ = 21040. Its totient is φ = 18900.

The previous prime is 19963. The next prime is 19973. The reversal of 19969 is 96991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 96991 = 23 ⋅4217.

It is a cyclic number.

It is not a de Polignac number, because 19969 - 2³ = 19961 is a prime.

It is a super-2 number, since 2×19969² = 797521922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 507 + ... + 544.

It is an arithmetic number, because the mean of its divisors is an integer number (5260).

It is a Proth number, since it is equal to 39 ⋅ 2⁹ + 1 and 39 < 2⁹.

2¹⁹⁹⁶⁹ is an apocalyptic number.

19969 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

19969 is a deficient number, since it is larger than the sum of its proper divisors (1071).

19969 is a wasteful number, since it uses less digits than its factorization.

19969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1070.

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

The square root of 19969 is about 141.3117121827. The cubic root of 19969 is about 27.1301444227.

It can be divided in two parts, 199 and 69, that multiplied together give a palindrome (13731).

The spelling of 19969 in words is "nineteen thousand, nine hundred sixty-nine".