21043634012 has 12 divisors (see below), whose sum is σ = 37190977656. Its totient is φ = 10417640400.

The previous prime is 21043634009. The next prime is 21043634107.

21043634012 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21043634012² (a number of 21 digits) contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 26043698 + ... + 26044505.

It is an arithmetic number, because the mean of its divisors is an integer number (3099248138).

Almost surely, 2^21043634012 is an apocalyptic number.

It is an amenable number.

21043634012 is a deficient number, since it is larger than the sum of its proper divisors (16147343644).

21043634012 is a wasteful number, since it uses less digits than its factorization.

21043634012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52088308 (or 52088306 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The spelling of 21043634012 in words is "twenty-one billion, forty-three million, six hundred thirty-four thousand, twelve".