1151261161 has 4 divisors (see below), whose sum is σ = 1161823300. Its totient is φ = 1140699024.

The previous prime is 1151261119. The next prime is 1151261171. The reversal of 1151261161 is 1611621511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1611621511 = 73 ⋅22077007.

It can be written as a sum of positive squares in 2 ways, for example, as 690901225 + 460359936 = 26285^2 + 21456^2 .

It is a cyclic number.

It is not a de Polignac number, because 1151261161 - 2¹¹ = 1151259113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1151261171) 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, 5280906 + ... + 5281123.

It is an arithmetic number, because the mean of its divisors is an integer number (290455825).

Almost surely, 2^1151261161 is an apocalyptic number.

It is an amenable number.

1151261161 is a deficient number, since it is larger than the sum of its proper divisors (10562139).

1151261161 is a wasteful number, since it uses less digits than its factorization.

1151261161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10562138.

The product of its digits is 360, while the sum is 25.

The square root of 1151261161 is about 33930.2396248538. The cubic root of 1151261161 is about 1048.0724002703.

Adding to 1151261161 its reverse (1611621511), we get a palindrome (2762882672).

The spelling of 1151261161 in words is "one billion, one hundred fifty-one million, two hundred sixty-one thousand, one hundred sixty-one".