21112012002120 has 256 divisors, whose sum is σ = 69496606126080. Its totient is φ = 5099320396800.

The previous prime is 21112012002101. The next prime is 21112012002127. The reversal of 21112012002120 is 2120021021112.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21112012002120.

It is not an unprimeable number, because it can be changed into a prime (21112012002127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 22918677 + ... + 23822043.

It is an arithmetic number, because the mean of its divisors is an integer number (271471117680).

Almost surely, 2^{21112012002120} is an apocalyptic number.

21112012002120 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 21112012002120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34748303063040).

21112012002120 is an abundant number, since it is smaller than the sum of its proper divisors (48384594123960).

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

21112012002120 is a wasteful number, since it uses less digits than its factorization.

21112012002120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 903676 (or 903672 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21112012002120 its reverse (2120021021112), we get a palindrome (23232033023232).

The spelling of 21112012002120 in words is "twenty-one trillion, one hundred twelve billion, twelve million, two thousand, one hundred twenty".