1155012011 has 4 divisors (see below), whose sum is σ = 1222953912. Its totient is φ = 1087070112.

The previous prime is 1155011993. The next prime is 1155012013. The reversal of 1155012011 is 1102105511.

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 1155012011 - 2⁶ = 1155011947 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 67941883 = 1155012011 / (1 + 1 + 5 + 5 + 0 + 1 + 2 + 0 + 1 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1155012013) 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, 33970925 + ... + 33970958.

It is an arithmetic number, because the mean of its divisors is an integer number (305738478).

Almost surely, 2^1155012011 is an apocalyptic number.

1155012011 is a deficient number, since it is larger than the sum of its proper divisors (67941901).

1155012011 is an equidigital number, since it uses as much as digits as its factorization.

1155012011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67941900.

The product of its (nonzero) digits is 50, while the sum is 17.

The square root of 1155012011 is about 33985.4676442741. The cubic root of 1155012011 is about 1049.2093854935.

Adding to 1155012011 its reverse (1102105511), we get a palindrome (2257117522).

The spelling of 1155012011 in words is "one billion, one hundred fifty-five million, twelve thousand, eleven".