10111122122221 has 2 divisors, whose sum is σ = 10111122122222. Its totient is φ = 10111122122220.

The previous prime is 10111122122173. The next prime is 10111122122239. The reversal of 10111122122221 is 12222122111101.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8248033619721 + 1863088502500 = 2871939^2 + 1364950^2 .

It is a cyclic number.

It is not a de Polignac number, because 10111122122221 - 2²⁹ = 10110585251309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10111122122261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5055561061110 + 5055561061111.

It is an arithmetic number, because the mean of its divisors is an integer number (5055561061111).

Almost surely, 2^{10111122122221} is an apocalyptic number.

It is an amenable number.

10111122122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

10111122122221 is an equidigital number, since it uses as much as digits as its factorization.

10111122122221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 10111122122221 its reverse (12222122111101), we get a palindrome (22333244233322).

The spelling of 10111122122221 in words is "ten trillion, one hundred eleven billion, one hundred twenty-two million, one hundred twenty-two thousand, two hundred twenty-one".