21212202221120 has 56 divisors (see below), whose sum is σ = 50573081594808. Its totient is φ = 8474545971200.

The previous prime is 21212202221113. The next prime is 21212202221129. The reversal of 21212202221120 is 2112220221212.

It can be written as a sum of positive squares in 4 ways, for example, as 5759692804096 + 15452509417024 = 2399936^2 + 3930968^2 .

It is a super-2 number, since 2×21212202221120² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21212202221092 and 21212202221101.

It is not an unprimeable number, because it can be changed into a prime (21212202221129) 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, 40107641 + ... + 40633080.

Almost surely, 2^{21212202221120} is an apocalyptic number.

21212202221120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212202221120 is an abundant number, since it is smaller than the sum of its proper divisors (29360879373688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21212202221120 is an equidigital number, since it uses as much as digits as its factorization.

21212202221120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80741559 (or 80741549 counting only the distinct ones).

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

Adding to 21212202221120 its reverse (2112220221212), we get a palindrome (23324422442332).

The spelling of 21212202221120 in words is "twenty-one trillion, two hundred twelve billion, two hundred two million, two hundred twenty-one thousand, one hundred twenty".