123505 has 8 divisors (see below), whose sum is σ = 157032. Its totient is φ = 92928.

The previous prime is 123503. The next prime is 123517. The reversal of 123505 is 505321.

123505 = 248² + 249².

It can be written as a sum of positive squares in 4 ways, for example, as 61504 + 62001 = 248^2 + 249^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 123505 - 2¹ = 123503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123503) 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, 642 + ... + 811.

It is an arithmetic number, because the mean of its divisors is an integer number (19629).

2¹²³⁵⁰⁵ is an apocalyptic number.

123505 is the 249-th centered square number.

It is an amenable number.

123505 is a deficient number, since it is larger than the sum of its proper divisors (33527).

123505 is a wasteful number, since it uses less digits than its factorization.

123505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1475.

The product of its (nonzero) digits is 150, while the sum is 16.

The square root of 123505 is about 351.4327816240. The cubic root of 123505 is about 49.7998666685.

Adding to 123505 its reverse (505321), we get a palindrome (628826).

The spelling of 123505 in words is "one hundred twenty-three thousand, five hundred five".