21021120221221 has 8 divisors (see below), whose sum is σ = 21077217469440. Its totient is φ = 20965029285312.

The previous prime is 21021120221197. The next prime is 21021120221263. The reversal of 21021120221221 is 12212202112012.

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 21021120221221 - 2⁴¹ = 18822096965669 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 (21021120281221) 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, 5129146 + ... + 8267428.

It is an arithmetic number, because the mean of its divisors is an integer number (2634652183680).

Almost surely, 2^{21021120221221} is an apocalyptic number.

It is an amenable number.

21021120221221 is a deficient number, since it is larger than the sum of its proper divisors (56097248219).

21021120221221 is a wasteful number, since it uses less digits than its factorization.

21021120221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3156155.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21021120221221 its reverse (12212202112012), we get a palindrome (33233322333233).

The spelling of 21021120221221 in words is "twenty-one trillion, twenty-one billion, one hundred twenty million, two hundred twenty-one thousand, two hundred twenty-one".