11561111 has 8 divisors (see below), whose sum is σ = 12480480. Its totient is φ = 10676512.

The previous prime is 11561089. The next prime is 11561117. The reversal of 11561111 is 11116511.

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 11561111 - 2¹⁴ = 11544727 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11561111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11561117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8000 + ... + 9333.

It is an arithmetic number, because the mean of its divisors is an integer number (1560060).

Almost surely, 2^11561111 is an apocalyptic number.

11561111 is a deficient number, since it is larger than the sum of its proper divisors (919369).

11561111 is a wasteful number, since it uses less digits than its factorization.

11561111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17385.

The product of its digits is 30, while the sum is 17.

The square root of 11561111 is about 3400.1633784276. The cubic root of 11561111 is about 226.1169872300.

Adding to 11561111 its reverse (11116511), we get a palindrome (22677622).

It can be divided in two parts, 115611 and 11, that multiplied together give a palindrome (1271721).

The spelling of 11561111 in words is "eleven million, five hundred sixty-one thousand, one hundred eleven".