21222021012221 has 8 divisors (see below), whose sum is σ = 21226098708864. Its totient is φ = 21217943659360.

The previous prime is 21222021012217. The next prime is 21222021012239. The reversal of 21222021012221 is 12221012022212.

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 21222021012221 - 2² = 21222021012217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21222021012193 and 21222021012202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222021072221) 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, 146558426 + ... + 146703156.

It is an arithmetic number, because the mean of its divisors is an integer number (2653262338608).

Almost surely, 2^{21222021012221} is an apocalyptic number.

It is an amenable number.

21222021012221 is a deficient number, since it is larger than the sum of its proper divisors (4077696643).

21222021012221 is a wasteful number, since it uses less digits than its factorization.

21222021012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171891.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21222021012221 its reverse (12221012022212), we get a palindrome (33443033034433).

The spelling of 21222021012221 in words is "twenty-one trillion, two hundred twenty-two billion, twenty-one million, twelve thousand, two hundred twenty-one".