12216061111561 has 16 divisors (see below), whose sum is σ = 13703590656000. Its totient is φ = 10834401325968.

The previous prime is 12216061111543. The next prime is 12216061111621. The reversal of 12216061111561 is 16511116061221.

It is not a de Polignac number, because 12216061111561 - 2¹¹ = 12216061109513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12216061111361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 297366411 + ... + 297407488.

It is an arithmetic number, because the mean of its divisors is an integer number (856474416000).

Almost surely, 2^{12216061111561} is an apocalyptic number.

It is an amenable number.

12216061111561 is a deficient number, since it is larger than the sum of its proper divisors (1487529544439).

12216061111561 is a wasteful number, since it uses less digits than its factorization.

12216061111561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594773988.

The product of its (nonzero) digits is 4320, while the sum is 34.

Adding to 12216061111561 its reverse (16511116061221), we get a palindrome (28727177172782).

The spelling of 12216061111561 in words is "twelve trillion, two hundred sixteen billion, sixty-one million, one hundred eleven thousand, five hundred sixty-one".