20121002122021 has 2 divisors, whose sum is σ = 20121002122022. Its totient is φ = 20121002122020.

The previous prime is 20121002122009. The next prime is 20121002122061. The reversal of 20121002122021 is 12022120012102.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20077837488900 + 43164633121 = 4480830^2 + 207761^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121002122021 - 2¹⁹ = 20121001597733 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20121002121986 and 20121002122004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20121002122061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060501061010 + 10060501061011.

It is an arithmetic number, because the mean of its divisors is an integer number (10060501061011).

Almost surely, 2^{20121002122021} is an apocalyptic number.

It is an amenable number.

20121002122021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121002122021 is an equidigital number, since it uses as much as digits as its factorization.

20121002122021 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 16.

Adding to 20121002122021 its reverse (12022120012102), we get a palindrome (32143122134123).

The spelling of 20121002122021 in words is "twenty trillion, one hundred twenty-one billion, two million, one hundred twenty-two thousand, twenty-one".