20211211121 has 2 divisors, whose sum is σ = 20211211122. Its totient is φ = 20211211120.

The previous prime is 20211211117. The next prime is 20211211123. The reversal of 20211211121 is 12111211202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15896166400 + 4315044721 = 126080^2 + 65689^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211211121 - 2² = 20211211117 is a prime.

Together with 20211211123, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20211211096 and 20211211105.

It is not a weakly prime, because it can be changed into another prime (20211211123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105605560 + 10105605561.

It is an arithmetic number, because the mean of its divisors is an integer number (10105605561).

Almost surely, 2^20211211121 is an apocalyptic number.

It is an amenable number.

20211211121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211211121 is an equidigital number, since it uses as much as digits as its factorization.

20211211121 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 14.

Adding to 20211211121 its reverse (12111211202), we get a palindrome (32322422323).

The spelling of 20211211121 in words is "twenty billion, two hundred eleven million, two hundred eleven thousand, one hundred twenty-one".