21121444120 has 96 divisors (see below), whose sum is σ = 55472331600. Its totient is φ = 7216726272.

The previous prime is 21121444067. The next prime is 21121444129. The reversal of 21121444120 is 2144412112.

It is a super-2 number, since 2×21121444120² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121444091 and 21121444100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121444129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 555891 + ... + 592669.

Almost surely, 2^21121444120 is an apocalyptic number.

21121444120 is a gapful number since it is divisible by the number (20) 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 21121444120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27736165800).

21121444120 is an abundant number, since it is smaller than the sum of its proper divisors (34350887480).

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

21121444120 is a wasteful number, since it uses less digits than its factorization.

21121444120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37097 (or 37086 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21121444120 its reverse (2144412112), we get a palindrome (23265856232).

The spelling of 21121444120 in words is "twenty-one billion, one hundred twenty-one million, four hundred forty-four thousand, one hundred twenty".