21220102201021 has 2 divisors, whose sum is σ = 21220102201022. Its totient is φ = 21220102201020.

The previous prime is 21220102200991. The next prime is 21220102201069. The reversal of 21220102201021 is 12010220102212.

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., 15643013765625 + 5577088435396 = 3955125^2 + 2361586^2 .

It is a cyclic number.

It is not a de Polignac number, because 21220102201021 - 2³⁹ = 20670346387133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21220102200986 and 21220102201004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220102205021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610051100510 + 10610051100511.

It is an arithmetic number, because the mean of its divisors is an integer number (10610051100511).

Almost surely, 2^{21220102201021} is an apocalyptic number.

It is an amenable number.

21220102201021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220102201021 is an equidigital number, since it uses as much as digits as its factorization.

21220102201021 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 21220102201021 its reverse (12010220102212), we get a palindrome (33230322303233).

The spelling of 21220102201021 in words is "twenty-one trillion, two hundred twenty billion, one hundred two million, two hundred one thousand, twenty-one".