21120202012 has 96 divisors (see below), whose sum is σ = 47134926720. Its totient is φ = 8054000640.

The previous prime is 21120202003. The next prime is 21120202057. The reversal of 21120202012 is 21020202112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 21120201983 and 21120202001.

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 31 ways as a sum of consecutive naturals, for example, 8665258 + ... + 8667694.

It is an arithmetic number, because the mean of its divisors is an integer number (490988820).

Almost surely, 2^21120202012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21120202012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23567463360).

21120202012 is an abundant number, since it is smaller than the sum of its proper divisors (26014724708).

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

21120202012 is a wasteful number, since it uses less digits than its factorization.

21120202012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3311 (or 3309 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21120202012 its reverse (21020202112), we get a palindrome (42140404124).

The spelling of 21120202012 in words is "twenty-one billion, one hundred twenty million, two hundred two thousand, twelve".