21211012002121 has 2 divisors, whose sum is σ = 21211012002122. Its totient is φ = 21211012002120.

The previous prime is 21211012002119. The next prime is 21211012002149. The reversal of 21211012002121 is 12120021011212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13926599930896 + 7284412071225 = 3731836^2 + 2698965^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211012002121 - 2¹ = 21211012002119 is a prime.

It is a super-2 number, since 2×21211012002121² (a number of 27 digits) contains 22 as substring.

Together with 21211012002119, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21211012002095 and 21211012002104.

It is not a weakly prime, because it can be changed into another prime (21211012602121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605506001060 + 10605506001061.

It is an arithmetic number, because the mean of its divisors is an integer number (10605506001061).

Almost surely, 2^{21211012002121} is an apocalyptic number.

It is an amenable number.

21211012002121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211012002121 is an equidigital number, since it uses as much as digits as its factorization.

21211012002121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21211012002121 its reverse (12120021011212), we get a palindrome (33331033013333).

Subtracting from 21211012002121 its reverse (12120021011212), we obtain a palindrome (9090990990909).

The spelling of 21211012002121 in words is "twenty-one trillion, two hundred eleven billion, twelve million, two thousand, one hundred twenty-one".