21222021021121 has 12 divisors (see below), whose sum is σ = 22554641597580. Its totient is φ = 19964068167680.

The previous prime is 21222021021119. The next prime is 21222021021127. The reversal of 21222021021121 is 12112012022212.

It can be written as a sum of positive squares in 6 ways, for example, as 3898902990096 + 17323118031025 = 1974564^2 + 4162105^2 .

It is not a de Polignac number, because 21222021021121 - 2¹ = 21222021021119 is a prime.

It is a super-2 number, since 2×21222021021121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21222021021127) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17042176 + ... + 18244993.

It is an arithmetic number, because the mean of its divisors is an integer number (1879553466465).

Almost surely, 2^{21222021021121} is an apocalyptic number.

It is an amenable number.

21222021021121 is a deficient number, since it is larger than the sum of its proper divisors (1332620576459).

21222021021121 is a wasteful number, since it uses less digits than its factorization.

21222021021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35289284 (or 35289267 counting only the distinct ones).

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

Adding to 21222021021121 its reverse (12112012022212), we get a palindrome (33334033043333).

The spelling of 21222021021121 in words is "twenty-one trillion, two hundred twenty-two billion, twenty-one million, twenty-one thousand, one hundred twenty-one".