2216561909 has 2 divisors, whose sum is σ = 2216561910. Its totient is φ = 2216561908.

The previous prime is 2216561903. The next prime is 2216561927. The reversal of 2216561909 is 9091656122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1572519025 + 644042884 = 39655^2 + 25378^2 .

It is a cyclic number.

It is not a de Polignac number, because 2216561909 - 2⁸ = 2216561653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2216561903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1108280954 + 1108280955.

It is an arithmetic number, because the mean of its divisors is an integer number (1108280955).

Almost surely, 2^2216561909 is an apocalyptic number.

It is an amenable number.

2216561909 is a deficient number, since it is larger than the sum of its proper divisors (1).

2216561909 is an equidigital number, since it uses as much as digits as its factorization.

2216561909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 2216561909 is about 47080.3771119136. The cubic root of 2216561909 is about 1303.8469694849.

The spelling of 2216561909 in words is "two billion, two hundred sixteen million, five hundred sixty-one thousand, nine hundred nine".