21101003330221 has 4 divisors (see below), whose sum is σ = 22342238820252. Its totient is φ = 19859767840192.

The previous prime is 21101003330207. The next prime is 21101003330233. The reversal of 21101003330221 is 12203330010112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17718122304100 + 3382881026121 = 4209290^2 + 1839261^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101003330221 - 2³⁷ = 20963564376749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101003630221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 620617744990 + ... + 620617745023.

It is an arithmetic number, because the mean of its divisors is an integer number (5585559705063).

Almost surely, 2^{21101003330221} is an apocalyptic number.

It is an amenable number.

21101003330221 is a deficient number, since it is larger than the sum of its proper divisors (1241235490031).

21101003330221 is a wasteful number, since it uses less digits than its factorization.

21101003330221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1241235490030.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21101003330221 its reverse (12203330010112), we get a palindrome (33304333340333).

The spelling of 21101003330221 in words is "twenty-one trillion, one hundred one billion, three million, three hundred thirty thousand, two hundred twenty-one".