21120120001021 has 2 divisors, whose sum is σ = 21120120001022. Its totient is φ = 21120120001020.

The previous prime is 21120120000983. The next prime is 21120120001033. The reversal of 21120120001021 is 12010002102112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10612700505796 + 10507419495225 = 3257714^2 + 3241515^2 .

It is a cyclic number.

It is not a de Polignac number, because 21120120001021 - 2²¹ = 21120117903869 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21120120000992 and 21120120001010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21120120001091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560060000510 + 10560060000511.

It is an arithmetic number, because the mean of its divisors is an integer number (10560060000511).

Almost surely, 2^{21120120001021} is an apocalyptic number.

It is an amenable number.

21120120001021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120120001021 is an equidigital number, since it uses as much as digits as its factorization.

21120120001021 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 21120120001021 its reverse (12010002102112), we get a palindrome (33130122103133).

The spelling of 21120120001021 in words is "twenty-one trillion, one hundred twenty billion, one hundred twenty million, one thousand, twenty-one".