2221100081 has 2 divisors, whose sum is σ = 2221100082. Its totient is φ = 2221100080.

The previous prime is 2221100071. The next prime is 2221100129. The reversal of 2221100081 is 1800011222.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1914850081 + 306250000 = 43759^2 + 17500^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2221100081 is a prime.

It is a super-2 number, since 2×2221100081² = 9866571139636413122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2221100071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1110550040 + 1110550041.

It is an arithmetic number, because the mean of its divisors is an integer number (1110550041).

Almost surely, 2^2221100081 is an apocalyptic number.

It is an amenable number.

2221100081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2221100081 is an equidigital number, since it uses as much as digits as its factorization.

2221100081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 2221100081 is about 47128.5484711762. The cubic root of 2221100081 is about 1304.7361916892.

The spelling of 2221100081 in words is "two billion, two hundred twenty-one million, one hundred thousand, eighty-one".