1155428123 has 4 divisors (see below), whose sum is σ = 1155496248. Its totient is φ = 1155360000.

The previous prime is 1155428107. The next prime is 1155428149. The reversal of 1155428123 is 3218245511.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1155428123 - 2⁴ = 1155428107 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1155428123.

It is not an unprimeable number, because it can be changed into a prime (1155458123) 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, 13748 + ... + 49998.

It is an arithmetic number, because the mean of its divisors is an integer number (288874062).

Almost surely, 2^1155428123 is an apocalyptic number.

1155428123 is a deficient number, since it is larger than the sum of its proper divisors (68125).

1155428123 is an equidigital number, since it uses as much as digits as its factorization.

1155428123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68124.

The product of its digits is 9600, while the sum is 32.

The square root of 1155428123 is about 33991.5890037521. The cubic root of 1155428123 is about 1049.3353686558.

The spelling of 1155428123 in words is "one billion, one hundred fifty-five million, four hundred twenty-eight thousand, one hundred twenty-three".