11115031261 has 4 divisors (see below), whose sum is σ = 11139038272. Its totient is φ = 11091024252.

The previous prime is 11115031229. The next prime is 11115031283. The reversal of 11115031261 is 16213051111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11115031261 - 2⁵ = 11115031229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11115031211) 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, 12002811 + ... + 12003736.

It is an arithmetic number, because the mean of its divisors is an integer number (2784759568).

Almost surely, 2^11115031261 is an apocalyptic number.

It is an amenable number.

11115031261 is a deficient number, since it is larger than the sum of its proper divisors (24007011).

11115031261 is an equidigital number, since it uses as much as digits as its factorization.

11115031261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24007010.

The product of its (nonzero) digits is 180, while the sum is 22.

Adding to 11115031261 its reverse (16213051111), we get a palindrome (27328082372).

The spelling of 11115031261 in words is "eleven billion, one hundred fifteen million, thirty-one thousand, two hundred sixty-one".