2216366561 has 12 divisors (see below), whose sum is σ = 2314698876. Its totient is φ = 2121425280.

The previous prime is 2216366533. The next prime is 2216366609. The reversal of 2216366561 is 1656636122.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1184736400 + 1031630161 = 34420^2 + 32119^2 .

It is not a de Polignac number, because 2216366561 - 2²² = 2212172257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2216366521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 76655 + ... + 101531.

It is an arithmetic number, because the mean of its divisors is an integer number (192891573).

Almost surely, 2^2216366561 is an apocalyptic number.

It is an amenable number.

2216366561 is a deficient number, since it is larger than the sum of its proper divisors (98332315).

2216366561 is an equidigital number, since it uses as much as digits as its factorization.

2216366561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25012 (or 24971 counting only the distinct ones).

The product of its digits is 77760, while the sum is 38.

The square root of 2216366561 is about 47078.3024439072. The cubic root of 2216366561 is about 1303.8086652115.

The spelling of 2216366561 in words is "two billion, two hundred sixteen million, three hundred sixty-six thousand, five hundred sixty-one".