193989 has 4 divisors (see below), whose sum is σ = 258656. Its totient is φ = 129324.

The previous prime is 193979. The next prime is 193993. The reversal of 193989 is 989391.

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.

It is not a de Polignac number, because 193989 - 2⁵ = 193957 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (193939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32329 + ... + 32334.

It is an arithmetic number, because the mean of its divisors is an integer number (64664).

2¹⁹³⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

193989 is a deficient number, since it is larger than the sum of its proper divisors (64667).

193989 is an equidigital number, since it uses as much as digits as its factorization.

193989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64666.

The product of its digits is 17496, while the sum is 39.

The square root of 193989 is about 440.4418236271. The cubic root of 193989 is about 57.8885095665. Note that the first 3 decimals are identical.

The spelling of 193989 in words is "one hundred ninety-three thousand, nine hundred eighty-nine".