21010222111221 has 48 divisors (see below), whose sum is σ = 34919911678080. Its totient is φ = 11924120263680.

The previous prime is 21010222111213. The next prime is 21010222111289. The reversal of 21010222111221 is 12211122201012.

21010222111221 is a `hidden beast` number, since 210 + 1 + 0 + 2 + 221 + 11 + 221 = 666.

It is not a de Polignac number, because 21010222111221 - 2³ = 21010222111213 is a prime.

It is a super-2 number, since 2×21010222111221² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21010222111194 and 21010222111203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010222111211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14517645 + ... + 15899133.

It is an arithmetic number, because the mean of its divisors is an integer number (727498159960).

Almost surely, 2^{21010222111221} is an apocalyptic number.

21010222111221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21010222111221 is a deficient number, since it is larger than the sum of its proper divisors (13909689566859).

21010222111221 is a wasteful number, since it uses less digits than its factorization.

21010222111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1383146 (or 1383143 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21010222111221 its reverse (12211122201012), we get a palindrome (33221344312233).

The spelling of 21010222111221 in words is "twenty-one trillion, ten billion, two hundred twenty-two million, one hundred eleven thousand, two hundred twenty-one".