221222122420 has 48 divisors (see below), whose sum is σ = 500462076240. Its totient is φ = 81655934976.

The previous prime is 221222122369. The next prime is 221222122423. The reversal of 221222122420 is 24221222122.

It can be written as a sum of positive squares in 8 ways, for example, as 16806011044 + 204416111376 = 129638^2 + 452124^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221222122391 and 221222122400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221222122423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 689694 + ... + 958186.

It is an arithmetic number, because the mean of its divisors is an integer number (10426293255).

Almost surely, 2^221222122420 is an apocalyptic number.

221222122420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221222122420 is an abundant number, since it is smaller than the sum of its proper divisors (279239953820).

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

221222122420 is a wasteful number, since it uses less digits than its factorization.

221222122420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271684 (or 271682 counting only the distinct ones).

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

Adding to 221222122420 its reverse (24221222122), we get a palindrome (245443344542).

The spelling of 221222122420 in words is "two hundred twenty-one billion, two hundred twenty-two million, one hundred twenty-two thousand, four hundred twenty".