12221000000 has 294 divisors, whose sum is σ = 33649608342. Its totient is φ = 4400000000.

The previous prime is 12220999991. The next prime is 12221000003. The reversal of 12221000000 is 12221.

It can be written as a sum of positive squares in 7 ways, for example, as 11413076224 + 807923776 = 106832^2 + 28424^2 .

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221000003) by changing a digit.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 120999950 + ... + 121000050.

Almost surely, 2^12221000000 is an apocalyptic number.

12221000000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12221000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16824804171).

12221000000 is an abundant number, since it is smaller than the sum of its proper divisors (21428608342).

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

12221000000 is an frugal number, since it uses more digits than its factorization.

12221000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 8.

Adding to 12221000000 its reverse (12221), we get a palindrome (12221012221).

Multiplying 12221000000 by its reverse (12221), we get a square (149352841000000 = 12221000²).

12221000000 divided by its reverse (12221) gives a 6-th power (1000000 = 10⁶).

The spelling of 12221000000 in words is "twelve billion, two hundred twenty-one million", and thus it is an aban number.