21064784832 has 420 divisors, whose sum is σ = 78237085080. Its totient is φ = 5554676736.

The previous prime is 21064784803. The next prime is 21064784849. The reversal of 21064784832 is 23848746012.

It is a happy number.

21064784832 is a `hidden beast` number, since 2 + 106 + 478 + 48 + 32 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 3299019 + ... + 3305397.

It is an arithmetic number, because the mean of its divisors is an integer number (186278774).

Almost surely, 2^21064784832 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21064784832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39118542540).

21064784832 is an abundant number, since it is smaller than the sum of its proper divisors (57172300248).

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

21064784832 is a wasteful number, since it uses less digits than its factorization.

21064784832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6430 (or 6404 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 45.

The spelling of 21064784832 in words is "twenty-one billion, sixty-four million, seven hundred eighty-four thousand, eight hundred thirty-two".