1155387123 has 24 divisors (see below), whose sum is σ = 1869821616. Its totient is φ = 681307200.

The previous prime is 1155387113. The next prime is 1155387127. The reversal of 1155387123 is 3217835511.

It is a happy number.

1155387123 is a `hidden beast` number, since 1 + 1 + 553 + 87 + 1 + 23 = 666.

It is not a de Polignac number, because 1155387123 - 2⁶ = 1155387059 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1155387127) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 154048 + ... + 161373.

It is an arithmetic number, because the mean of its divisors is an integer number (77909234).

Almost surely, 2^1155387123 is an apocalyptic number.

1155387123 is a deficient number, since it is larger than the sum of its proper divisors (714434493).

1155387123 is a wasteful number, since it uses less digits than its factorization.

1155387123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315475 (or 315472 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 1155387123 is about 33990.9859080316. The cubic root of 1155387123 is about 1049.3229567315.

The spelling of 1155387123 in words is "one billion, one hundred fifty-five million, three hundred eighty-seven thousand, one hundred twenty-three".