21906803891750 has 64 divisors (see below), whose sum is σ = 42693875452800. Its totient is φ = 8406669398400.

The previous prime is 21906803891741. The next prime is 21906803891803. The reversal of 21906803891750 is 5719830860912.

It is a self number, because there is not a number n which added to its sum of digits gives 21906803891750.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 8484770 + ... + 10761269.

It is an arithmetic number, because the mean of its divisors is an integer number (667091803950).

Almost surely, 2^{21906803891750} is an apocalyptic number.

21906803891750 is a deficient number, since it is larger than the sum of its proper divisors (20787071561050).

21906803891750 is a wasteful number, since it uses less digits than its factorization.

21906803891750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19246242 (or 19246232 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 59.

The spelling of 21906803891750 in words is "twenty-one trillion, nine hundred six billion, eight hundred three million, eight hundred ninety-one thousand, seven hundred fifty".