12116561 has 8 divisors (see below), whose sum is σ = 12776064. Its totient is φ = 11468160.

The previous prime is 12116557. The next prime is 12116569. The reversal of 12116561 is 16561121.

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 12116561 - 2² = 12116557 is a prime.

It is a super-2 number, since 2×12116561² = 293622100933442, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is not an unprimeable number, because it can be changed into a prime (12116569) 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, 485 + ... + 4946.

It is an arithmetic number, because the mean of its divisors is an integer number (1597008).

Almost surely, 2^12116561 is an apocalyptic number.

It is an amenable number.

12116561 is a deficient number, since it is larger than the sum of its proper divisors (659503).

12116561 is an equidigital number, since it uses as much as digits as its factorization.

It is an anagram of its base 8 representation: 12116561 = (56161121)₈.

12116561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5551.

The product of its digits is 360, while the sum is 23.

The square root of 12116561 is about 3480.8850885946. The cubic root of 12116561 is about 229.6817337100.

Adding to 12116561 its reverse (16561121), we get a palindrome (28677682).

The spelling of 12116561 in words is "twelve million, one hundred sixteen thousand, five hundred sixty-one".