1210011221 has 2 divisors, whose sum is σ = 1210011222. Its totient is φ = 1210011220.

The previous prime is 1210011217. The next prime is 1210011247. The reversal of 1210011221 is 1221100121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 869424196 + 340587025 = 29486^2 + 18455^2 .

It is an emirp because it is prime and its reverse (1221100121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1210011221 - 2² = 1210011217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1210011211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605005610 + 605005611.

It is an arithmetic number, because the mean of its divisors is an integer number (605005611).

Almost surely, 2^1210011221 is an apocalyptic number.

It is an amenable number.

1210011221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1210011221 is an equidigital number, since it uses as much as digits as its factorization.

1210011221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1210011221 is about 34785.2155520129. The cubic root of 1210011221 is about 1065.6055307296.

Adding to 1210011221 its reverse (1221100121), we get a palindrome (2431111342).

Subtracting 1210011221 from its reverse (1221100121), we obtain a square (11088900 = 3330²).

The spelling of 1210011221 in words is "one billion, two hundred ten million, eleven thousand, two hundred twenty-one".