21010120202221 has 8 divisors (see below), whose sum is σ = 21182791878144. Its totient is φ = 20838101350080.

The previous prime is 21010120202087. The next prime is 21010120202233. The reversal of 21010120202221 is 12220202101012.

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 21010120202221 - 2³⁹ = 20460364388333 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21010120202195 and 21010120202204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010120502221) 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, 163141315 + ... + 163270048.

It is an arithmetic number, because the mean of its divisors is an integer number (2647848984768).

Almost surely, 2^{21010120202221} is an apocalyptic number.

It is an amenable number.

21010120202221 is a deficient number, since it is larger than the sum of its proper divisors (172671675923).

21010120202221 is a wasteful number, since it uses less digits than its factorization.

21010120202221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326411891.

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

Adding to 21010120202221 its reverse (12220202101012), we get a palindrome (33230322303233).

The spelling of 21010120202221 in words is "twenty-one trillion, ten billion, one hundred twenty million, two hundred two thousand, two hundred twenty-one".