193905 has 24 divisors (see below), whose sum is σ = 349440. Its totient is φ = 99360.

The previous prime is 193891. The next prime is 193937. The reversal of 193905 is 509391.

It is not a de Polignac number, because 193905 - 2⁵ = 193873 is a prime.

193905 is a lucky number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 1326 + ... + 1464.

It is an arithmetic number, because the mean of its divisors is an integer number (14560).

2¹⁹³⁹⁰⁵ is an apocalyptic number.

193905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

193905 is a deficient number, since it is larger than the sum of its proper divisors (155535).

193905 is a wasteful number, since it uses less digits than its factorization.

193905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 1215, while the sum is 27.

The square root of 193905 is about 440.3464545105. The cubic root of 193905 is about 57.8801528438.

The spelling of 193905 in words is "one hundred ninety-three thousand, nine hundred five".