21203221122 has 48 divisors (see below), whose sum is σ = 47745210240. Its totient is φ = 7052400432.

The previous prime is 21203221103. The next prime is 21203221159. The reversal of 21203221122 is 22112230212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21203221095 and 21203221104.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 177904 + ... + 272132.

It is an arithmetic number, because the mean of its divisors is an integer number (994691880).

Almost surely, 2^21203221122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21203221122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23872605120).

21203221122 is an abundant number, since it is smaller than the sum of its proper divisors (26541989118).

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

21203221122 is an equidigital number, since it uses as much as digits as its factorization.

21203221122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94709 (or 94697 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21203221122 its reverse (22112230212), we get a palindrome (43315451334).

The spelling of 21203221122 in words is "twenty-one billion, two hundred three million, two hundred twenty-one thousand, one hundred twenty-two".