21221020010221 has 8 divisors (see below), whose sum is σ = 21285106164000. Its totient is φ = 21156952605360.

The previous prime is 21221020010173. The next prime is 21221020010249. The reversal of 21221020010221 is 12201002012212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21221020010221 - 2¹¹ = 21221020008173 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221020010195 and 21221020010204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221020011221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2418451 + ... + 6949168.

It is an arithmetic number, because the mean of its divisors is an integer number (2660638270500).

Almost surely, 2^{21221020010221} is an apocalyptic number.

It is an amenable number.

21221020010221 is a deficient number, since it is larger than the sum of its proper divisors (64086153779).

21221020010221 is an equidigital number, since it uses as much as digits as its factorization.

21221020010221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9374459.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21221020010221 its reverse (12201002012212), we get a palindrome (33422022022433).

The spelling of 21221020010221 in words is "twenty-one trillion, two hundred twenty-one billion, twenty million, ten thousand, two hundred twenty-one".