123205 has 8 divisors (see below), whose sum is σ = 151704. Its totient is φ = 96000.

The previous prime is 123203. The next prime is 123209. The reversal of 123205 is 502321.

It can be written as a sum of positive squares in 4 ways, for example, as 6241 + 116964 = 79^2 + 342^2 .

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

It is not a de Polignac number, because 123205 - 2¹ = 123203 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96 + ... + 505.

It is an arithmetic number, because the mean of its divisors is an integer number (18963).

2¹²³²⁰⁵ is an apocalyptic number.

It is an amenable number.

123205 is a deficient number, since it is larger than the sum of its proper divisors (28499).

123205 is an equidigital number, since it uses as much as digits as its factorization.

123205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647.

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 123205 is about 351.0056979594. The cubic root of 123205 is about 49.7595118299.

Adding to 123205 its reverse (502321), we get a palindrome (625526).

The spelling of 123205 in words is "one hundred twenty-three thousand, two hundred five".