212001121021 has 2 divisors, whose sum is σ = 212001121022. Its totient is φ = 212001121020.

The previous prime is 212001120971. The next prime is 212001121049. The reversal of 212001121021 is 120121100212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198839295396 + 13161825625 = 445914^2 + 114725^2 .

It is a cyclic number.

It is not a de Polignac number, because 212001121021 - 2⁷ = 212001120893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212001120992 and 212001121010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212001121051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106000560510 + 106000560511.

It is an arithmetic number, because the mean of its divisors is an integer number (106000560511).

Almost surely, 2^212001121021 is an apocalyptic number.

It is an amenable number.

212001121021 is a deficient number, since it is larger than the sum of its proper divisors (1).

212001121021 is an equidigital number, since it uses as much as digits as its factorization.

212001121021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 212001121021 its reverse (120121100212), we get a palindrome (332122221233).

The spelling of 212001121021 in words is "two hundred twelve billion, one million, one hundred twenty-one thousand, twenty-one".