2215663223561 has 2 divisors, whose sum is σ = 2215663223562. Its totient is φ = 2215663223560.

The previous prime is 2215663223519. The next prime is 2215663223563. The reversal of 2215663223561 is 1653223665122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2101864947961 + 113798275600 = 1449781^2 + 337340^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2215663223561 is a prime.

Together with 2215663223563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2215663223563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1107831611780 + 1107831611781.

It is an arithmetic number, because the mean of its divisors is an integer number (1107831611781).

Almost surely, 2^{2215663223561} is an apocalyptic number.

It is an amenable number.

2215663223561 is a deficient number, since it is larger than the sum of its proper divisors (1).

2215663223561 is an equidigital number, since it uses as much as digits as its factorization.

2215663223561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 777600, while the sum is 44.

Adding to 2215663223561 its reverse (1653223665122), we get a palindrome (3868886888683).

The spelling of 2215663223561 in words is "two trillion, two hundred fifteen billion, six hundred sixty-three million, two hundred twenty-three thousand, five hundred sixty-one".