305123 has 12 divisors (see below), whose sum is σ = 383040. Its totient is φ = 240912.

The previous prime is 305119. The next prime is 305131. The reversal of 305123 is 321503.

It is not a de Polignac number, because 305123 - 2² = 305119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 305098 and 305107.

It is not an unprimeable number, because it can be changed into a prime (305113) 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 11 ways as a sum of consecutive naturals, for example, 398 + ... + 876.

It is an arithmetic number, because the mean of its divisors is an integer number (31920).

2³⁰⁵¹²³ is an apocalyptic number.

305123 is a deficient number, since it is larger than the sum of its proper divisors (77917).

305123 is a wasteful number, since it uses less digits than its factorization.

305123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506 (or 499 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 14.

The square root of 305123 is about 552.3793986021. The cubic root of 305123 is about 67.3222024102.

Adding to 305123 its reverse (321503), we get a palindrome (626626).

The spelling of 305123 in words is "three hundred five thousand, one hundred twenty-three".