1211000221021 has 2 divisors, whose sum is σ = 1211000221022. Its totient is φ = 1211000221020.

The previous prime is 1211000221009. The next prime is 1211000221033. The reversal of 1211000221021 is 1201220001121.

It is a balanced prime because it is at equal distance from previous prime (1211000221009) and next prime (1211000221033).

It can be written as a sum of positive squares in only one way, i.e., 923355715396 + 287644505625 = 960914^2 + 536325^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211000221021 - 2⁷ = 1211000220893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211000220992 and 1211000221010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211000261021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605500110510 + 605500110511.

It is an arithmetic number, because the mean of its divisors is an integer number (605500110511).

Almost surely, 2^{1211000221021} is an apocalyptic number.

It is an amenable number.

1211000221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211000221021 is an equidigital number, since it uses as much as digits as its factorization.

1211000221021 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 13.

Adding to 1211000221021 its reverse (1201220001121), we get a palindrome (2412220222142).

The spelling of 1211000221021 in words is "one trillion, two hundred eleven billion, two hundred twenty-one thousand, twenty-one".