21221202112 has 112 divisors (see below), whose sum is σ = 46704040704. Its totient is φ = 9486720000.

The previous prime is 21221202109. The next prime is 21221202131. The reversal of 21221202112 is 21120212212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11589037 + ... + 11590867.

Almost surely, 2^21221202112 is an apocalyptic number.

21221202112 is a gapful number since it is divisible by the number (22) 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 21221202112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23352020352).

21221202112 is an abundant number, since it is smaller than the sum of its proper divisors (25482838592).

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

21221202112 is a wasteful number, since it uses less digits than its factorization.

21221202112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2118 (or 2108 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21221202112 its reverse (21120212212), we get a palindrome (42341414324).

The spelling of 21221202112 in words is "twenty-one billion, two hundred twenty-one million, two hundred two thousand, one hundred twelve".