123805 has 8 divisors (see below), whose sum is σ = 162144. Its totient is φ = 90000.

The previous prime is 123803. The next prime is 123817. The reversal of 123805 is 508321.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 123805 - 2¹ = 123803 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123803) 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 7 ways as a sum of consecutive naturals, for example, 1071 + ... + 1180.

It is an arithmetic number, because the mean of its divisors is an integer number (20268).

2¹²³⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

123805 is a deficient number, since it is larger than the sum of its proper divisors (38339).

123805 is a wasteful number, since it uses less digits than its factorization.

123805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2267.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 123805 is about 351.8593468987. The cubic root of 123805 is about 49.8401562105.

The spelling of 123805 in words is "one hundred twenty-three thousand, eight hundred five".