21043212108 has 96 divisors (see below), whose sum is σ = 50997945600. Its totient is φ = 6750019584.

The previous prime is 21043212103. The next prime is 21043212109. The reversal of 21043212108 is 80121234012.

21043212108 is nontrivially palindromic in base 9.

It is not an unprimeable number, because it can be changed into a prime (21043212103) 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 31 ways as a sum of consecutive naturals, for example, 6638748 + ... + 6641916.

It is an arithmetic number, because the mean of its divisors is an integer number (531228600).

Almost surely, 2^21043212108 is an apocalyptic number.

It is an amenable number.

21043212108 is an abundant number, since it is smaller than the sum of its proper divisors (29954733492).

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

21043212108 is a wasteful number, since it uses less digits than its factorization.

21043212108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3431 (or 3429 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The spelling of 21043212108 in words is "twenty-one billion, forty-three million, two hundred twelve thousand, one hundred eight".