21120000240 has 320 divisors, whose sum is σ = 72245376000. Its totient is φ = 5080154112.

The previous prime is 21120000227. The next prime is 21120000287. The reversal of 21120000240 is 4200002112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 36602832 + ... + 36603408.

It is an arithmetic number, because the mean of its divisors is an integer number (225766800).

Almost surely, 2^21120000240 is an apocalyptic number.

21120000240 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 21120000240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36122688000).

21120000240 is an abundant number, since it is smaller than the sum of its proper divisors (51125375760).

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

21120000240 is a wasteful number, since it uses less digits than its factorization.

21120000240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 984 (or 978 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21120000240 its reverse (4200002112), we get a palindrome (25320002352).

The spelling of 21120000240 in words is "twenty-one billion, one hundred twenty million, two hundred forty", and thus it is an aban number.