20002121220121 has 2 divisors, whose sum is σ = 20002121220122. Its totient is φ = 20002121220120.

The previous prime is 20002121220083. The next prime is 20002121220127. The reversal of 20002121220121 is 12102212120002.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15568043444496 + 4434077775625 = 3945636^2 + 2105725^2 .

It is a cyclic number.

It is not a de Polignac number, because 20002121220121 - 2⁹ = 20002121219609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20002121220095 and 20002121220104.

It is not a weakly prime, because it can be changed into another prime (20002121220127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10001060610060 + 10001060610061.

It is an arithmetic number, because the mean of its divisors is an integer number (10001060610061).

Almost surely, 2^{20002121220121} is an apocalyptic number.

It is an amenable number.

20002121220121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20002121220121 is an equidigital number, since it uses as much as digits as its factorization.

20002121220121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 20002121220121 its reverse (12102212120002), we get a palindrome (32104333340123).

The spelling of 20002121220121 in words is "twenty trillion, two billion, one hundred twenty-one million, two hundred twenty thousand, one hundred twenty-one".