123205305 has 16 divisors (see below), whose sum is σ = 197409024. Its totient is φ = 65616000.

The previous prime is 123205289. The next prime is 123205321. The reversal of 123205305 is 503502321.

It is an interprime number because it is at equal distance from previous prime (123205289) and next prime (123205321).

It is not a de Polignac number, because 123205305 - 2⁴ = 123205289 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5797 + ... + 16733.

It is an arithmetic number, because the mean of its divisors is an integer number (12338064).

Almost surely, 2^123205305 is an apocalyptic number.

123205305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

123205305 is a deficient number, since it is larger than the sum of its proper divisors (74203719).

123205305 is a wasteful number, since it uses less digits than its factorization.

123205305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11696.

The product of its (nonzero) digits is 900, while the sum is 21.

The square root of 123205305 is about 11099.7885114988. The cubic root of 123205305 is about 497.5955289061.

Adding to 123205305 its reverse (503502321), we get a palindrome (626707626).

The spelling of 123205305 in words is "one hundred twenty-three million, two hundred five thousand, three hundred five".