2221217917 has 2 divisors, whose sum is σ = 2221217918. Its totient is φ = 2221217916.

The previous prime is 2221217897. The next prime is 2221217923. The reversal of 2221217917 is 7197121222.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2206556676 + 14661241 = 46974^2 + 3829^2 .

It is a cyclic number.

It is not a de Polignac number, because 2221217917 - 2¹⁵ = 2221185149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2221217987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1110608958 + 1110608959.

It is an arithmetic number, because the mean of its divisors is an integer number (1110608959).

Almost surely, 2^2221217917 is an apocalyptic number.

It is an amenable number.

2221217917 is a deficient number, since it is larger than the sum of its proper divisors (1).

2221217917 is an equidigital number, since it uses as much as digits as its factorization.

2221217917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7056, while the sum is 34.

The square root of 2221217917 is about 47129.7986097968. The cubic root of 2221217917 is about 1304.7592646665.

The spelling of 2221217917 in words is "two billion, two hundred twenty-one million, two hundred seventeen thousand, nine hundred seventeen".