21222220221220 has 48 divisors (see below), whose sum is σ = 44675881060608. Its totient is φ = 8468104858880.

The previous prime is 21222220221179. The next prime is 21222220221233. The reversal of 21222220221220 is 2212202222212.

It is a super-2 number, since 2×21222220221220² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21222220221191 and 21222220221200.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16109880 + ... + 17377360.

It is an arithmetic number, because the mean of its divisors is an integer number (930747522096).

Almost surely, 2^{21222220221220} is an apocalyptic number.

21222220221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222220221220 is an abundant number, since it is smaller than the sum of its proper divisors (23453660839388).

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

21222220221220 is a wasteful number, since it uses less digits than its factorization.

21222220221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1269540 (or 1269538 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 22.

Adding to 21222220221220 its reverse (2212202222212), we get a palindrome (23434422443432).

The spelling of 21222220221220 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred twenty million, two hundred twenty-one thousand, two hundred twenty".