21066530730 has 192 divisors, whose sum is σ = 61633025280. Its totient is φ = 4513406976.

The previous prime is 21066530729. The next prime is 21066530741. The reversal of 21066530730 is 3703566012.

It is a junction number, because it is equal to n+sod(n) for n = 21066530691 and 21066530700.

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, 18995416 + ... + 18996524.

It is an arithmetic number, because the mean of its divisors is an integer number (321005340).

Almost surely, 2^21066530730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21066530730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30816512640).

21066530730 is an abundant number, since it is smaller than the sum of its proper divisors (40566494550).

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

21066530730 is a wasteful number, since it uses less digits than its factorization.

21066530730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1473 (or 1456 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 33.

The spelling of 21066530730 in words is "twenty-one billion, sixty-six million, five hundred thirty thousand, seven hundred thirty".