1155554321 has 4 divisors (see below), whose sum is σ = 1155642852. Its totient is φ = 1155465792.

The previous prime is 1155554299. The next prime is 1155554341. The reversal of 1155554321 is 1234555511.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1234555511 = 7 ⋅176365073.

It can be written as a sum of positive squares in 2 ways, for example, as 1065304321 + 90250000 = 32639^2 + 9500^2 .

It is a cyclic number.

It is not a de Polignac number, because 1155554321 - 2¹⁰ = 1155553297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1155554341) 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 3 ways as a sum of consecutive naturals, for example, 20396 + ... + 52221.

It is an arithmetic number, because the mean of its divisors is an integer number (288910713).

Almost surely, 2^1155554321 is an apocalyptic number.

It is an amenable number.

1155554321 is a deficient number, since it is larger than the sum of its proper divisors (88531).

1155554321 is an equidigital number, since it uses as much as digits as its factorization.

1155554321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88530.

The product of its digits is 15000, while the sum is 32.

The square root of 1155554321 is about 33993.4452652272. The cubic root of 1155554321 is about 1049.3735707159.

The spelling of 1155554321 in words is "one billion, one hundred fifty-five million, five hundred fifty-four thousand, three hundred twenty-one".