100000221221 has 2 divisors, whose sum is σ = 100000221222. Its totient is φ = 100000221220.

The previous prime is 100000221193. The next prime is 100000221257. The reversal of 100000221221 is 122122000001.

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., 91271056321 + 8729164900 = 302111^2 + 93430^2 .

It is a cyclic number.

It is not a de Polignac number, because 100000221221 - 2¹⁰ = 100000220197 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100000227221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50000110610 + 50000110611.

It is an arithmetic number, because the mean of its divisors is an integer number (50000110611).

Almost surely, 2^100000221221 is an apocalyptic number.

It is an amenable number.

100000221221 is a deficient number, since it is larger than the sum of its proper divisors (1).

100000221221 is an equidigital number, since it uses as much as digits as its factorization.

100000221221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 100000221221 its reverse (122122000001), we get a palindrome (222122221222).

The spelling of 100000221221 in words is "one hundred billion, two hundred twenty-one thousand, two hundred twenty-one".