21211000201021 has 2 divisors, whose sum is σ = 21211000201022. Its totient is φ = 21211000201020.

The previous prime is 21211000200979. The next prime is 21211000201037. The reversal of 21211000201021 is 12010200011212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20688761280100 + 522238920921 = 4548490^2 + 722661^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211000201021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211000200992 and 21211000201010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21211000201121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605500100510 + 10605500100511.

It is an arithmetic number, because the mean of its divisors is an integer number (10605500100511).

Almost surely, 2^{21211000201021} is an apocalyptic number.

It is an amenable number.

21211000201021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211000201021 is an equidigital number, since it uses as much as digits as its factorization.

21211000201021 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 21211000201021 its reverse (12010200011212), we get a palindrome (33221200212233).

The spelling of 21211000201021 in words is "twenty-one trillion, two hundred eleven billion, two hundred one thousand, twenty-one".