12216566215631 has 4 divisors (see below), whose sum is σ = 12216702600672. Its totient is φ = 12216429830592.

The previous prime is 12216566215621. The next prime is 12216566215657. The reversal of 12216566215631 is 13651266561221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12216566215631 is a prime.

It is a super-2 number, since 2×12216566215631² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12216566215621) 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, 68058071 + ... + 68237336.

It is an arithmetic number, because the mean of its divisors is an integer number (3054175650168).

Almost surely, 2^{12216566215631} is an apocalyptic number.

12216566215631 is a deficient number, since it is larger than the sum of its proper divisors (136385041).

12216566215631 is an equidigital number, since it uses as much as digits as its factorization.

12216566215631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136385040.

The product of its digits is 777600, while the sum is 47.

The spelling of 12216566215631 in words is "twelve trillion, two hundred sixteen billion, five hundred sixty-six million, two hundred fifteen thousand, six hundred thirty-one".