1155511649 has 4 divisors (see below), whose sum is σ = 1156134420. Its totient is φ = 1154888880.

The previous prime is 1155511631. The next prime is 1155511667. The reversal of 1155511649 is 9461155511.

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

It is an interprime number because it is at equal distance from previous prime (1155511631) and next prime (1155511667).

It can be written as a sum of positive squares in 2 ways, for example, as 414855424 + 740656225 = 20368^2 + 27215^2 .

It is a cyclic number.

It is not a de Polignac number, because 1155511649 - 2²⁰ = 1154463073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1155511249) 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, 308594 + ... + 312315.

It is an arithmetic number, because the mean of its divisors is an integer number (289033605).

Almost surely, 2^1155511649 is an apocalyptic number.

It is an amenable number.

1155511649 is a deficient number, since it is larger than the sum of its proper divisors (622771).

1155511649 is an equidigital number, since it uses as much as digits as its factorization.

1155511649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 622770.

The product of its digits is 27000, while the sum is 38.

The square root of 1155511649 is about 33992.8176090185. The cubic root of 1155511649 is about 1049.3606535616.

The spelling of 1155511649 in words is "one billion, one hundred fifty-five million, five hundred eleven thousand, six hundred forty-nine".