21693893760 has 768 divisors, whose sum is σ = 95754597120. Its totient is φ = 4394188800.

The previous prime is 21693893759. The next prime is 21693893807. The reversal of 21693893760 is 6739839612.

It is a junction number, because it is equal to n+sod(n) for n = 21693893697 and 21693893706.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 18183724 + ... + 18184916.

It is an arithmetic number, because the mean of its divisors is an integer number (124680465).

Almost surely, 2^21693893760 is an apocalyptic number.

21693893760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21693893760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47877298560).

21693893760 is an abundant number, since it is smaller than the sum of its proper divisors (74060703360).

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

21693893760 is a wasteful number, since it uses less digits than its factorization.

21693893760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277 (or 1262 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 54.

The spelling of 21693893760 in words is "twenty-one billion, six hundred ninety-three million, eight hundred ninety-three thousand, seven hundred sixty".