11111105561 has 8 divisors (see below), whose sum is σ = 11184625344. Its totient is φ = 11037620880.

The previous prime is 11111105549. The next prime is 11111105569. The reversal of 11111105561 is 16550111111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11111105561 - 2¹⁸ = 11110843417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11111105569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1013636 + ... + 1024538.

It is an arithmetic number, because the mean of its divisors is an integer number (1398078168).

Almost surely, 2^11111105561 is an apocalyptic number.

It is an amenable number.

11111105561 is a deficient number, since it is larger than the sum of its proper divisors (73519783).

11111105561 is a wasteful number, since it uses less digits than its factorization.

11111105561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17551.

The product of its (nonzero) digits is 150, while the sum is 23.

Adding to 11111105561 its reverse (16550111111), we get a palindrome (27661216672).

The spelling of 11111105561 in words is "eleven billion, one hundred eleven million, one hundred five thousand, five hundred sixty-one".