155123 has 4 divisors (see below), whose sum is σ = 157728. Its totient is φ = 152520.

The previous prime is 155119. The next prime is 155137. The reversal of 155123 is 321551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 321551 = 53 ⋅6067.

It is a cyclic number.

It is not a de Polignac number, because 155123 - 2² = 155119 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155153) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1211 + ... + 1332.

It is an arithmetic number, because the mean of its divisors is an integer number (39432).

2¹⁵⁵¹²³ is an apocalyptic number.

155123 is a deficient number, since it is larger than the sum of its proper divisors (2605).

155123 is an equidigital number, since it uses as much as digits as its factorization.

155123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2604.

The product of its digits is 150, while the sum is 17.

The square root of 155123 is about 393.8565728790. The cubic root of 155123 is about 53.7310587668.

Adding to 155123 its reverse (321551), we get a palindrome (476674).

The spelling of 155123 in words is "one hundred fifty-five thousand, one hundred twenty-three".