21331320120 has 192 divisors, whose sum is σ = 75715417440. Its totient is φ = 5165337600.

The previous prime is 21331320079. The next prime is 21331320137. The reversal of 21331320120 is 2102313312.

21331320120 is a `hidden beast` number, since 2 + 1 + 331 + 320 + 12 + 0 = 666.

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 = 21331320093 and 21331320102.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 4199022 + ... + 4204098.

Almost surely, 2^21331320120 is an apocalyptic number.

21331320120 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 21331320120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37857708720).

21331320120 is an abundant number, since it is smaller than the sum of its proper divisors (54384097320).

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

21331320120 is a wasteful number, since it uses less digits than its factorization.

21331320120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6166 (or 6159 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21331320120 its reverse (2102313312), we get a palindrome (23433633432).

The spelling of 21331320120 in words is "twenty-one billion, three hundred thirty-one million, three hundred twenty thousand, one hundred twenty".