1211112021121 has 2 divisors, whose sum is σ = 1211112021122. Its totient is φ = 1211112021120.

The previous prime is 1211112021043. The next prime is 1211112021143. The reversal of 1211112021121 is 1211202111121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 671711376400 + 539400644721 = 819580^2 + 734439^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211112021121 - 2²³ = 1211103632513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211112021095 and 1211112021104.

It is not a weakly prime, because it can be changed into another prime (1211112721121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605556010560 + 605556010561.

It is an arithmetic number, because the mean of its divisors is an integer number (605556010561).

Almost surely, 2^{1211112021121} is an apocalyptic number.

It is an amenable number.

1211112021121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211112021121 is an equidigital number, since it uses as much as digits as its factorization.

1211112021121 is an odious number, because the sum of its binary digits is odd.

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

Adding to 1211112021121 its reverse (1211202111121), we get a palindrome (2422314132242).

The spelling of 1211112021121 in words is "one trillion, two hundred eleven billion, one hundred twelve million, twenty-one thousand, one hundred twenty-one".