1155523123 has 4 divisors (see below), whose sum is σ = 1166964048. Its totient is φ = 1144082200.

The previous prime is 1155523111. The next prime is 1155523139. The reversal of 1155523123 is 3213255511.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1155523123 - 2⁵ = 1155523091 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1155523091 and 1155523100.

It is not an unprimeable number, because it can be changed into a prime (1155523163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5720311 + ... + 5720512.

It is an arithmetic number, because the mean of its divisors is an integer number (291741012).

Almost surely, 2^1155523123 is an apocalyptic number.

1155523123 is a deficient number, since it is larger than the sum of its proper divisors (11440925).

1155523123 is a wasteful number, since it uses less digits than its factorization.

1155523123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11440924.

The product of its digits is 4500, while the sum is 28.

The square root of 1155523123 is about 33992.9863795460. The cubic root of 1155523123 is about 1049.3641268641.

Adding to 1155523123 its reverse (3213255511), we get a palindrome (4368778634).

The spelling of 1155523123 in words is "one billion, one hundred fifty-five million, five hundred twenty-three thousand, one hundred twenty-three".