21568944750 has 64 divisors (see below), whose sum is σ = 53870558976. Its totient is φ = 5748036000.

The previous prime is 21568944739. The next prime is 21568944767. The reversal of 21568944750 is 5744986512.

It is a junction number, because it is equal to n+sod(n) for n = 21568944693 and 21568944702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1283905 + ... + 1300595.

It is an arithmetic number, because the mean of its divisors is an integer number (841727484).

Almost surely, 2^21568944750 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21568944750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26935279488).

21568944750 is an abundant number, since it is smaller than the sum of its proper divisors (32301614226).

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

21568944750 is a wasteful number, since it uses less digits than its factorization.

21568944750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18434 (or 18424 counting only the distinct ones).

The product of its (nonzero) digits is 2419200, while the sum is 51.

The spelling of 21568944750 in words is "twenty-one billion, five hundred sixty-eight million, nine hundred forty-four thousand, seven hundred fifty".