21947684832 has 240 divisors, whose sum is σ = 66182764032. Its totient is φ = 7132769280.

The previous prime is 21947684831. The next prime is 21947684897. The reversal of 21947684832 is 23848674912.

21947684832 is a `hidden beast` number, since 2 + 1 + 94 + 76 + 8 + 483 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21947684831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20079678 + ... + 20080770.

Almost surely, 2^21947684832 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 21947684832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33091382016).

21947684832 is an abundant number, since it is smaller than the sum of its proper divisors (44235079200).

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

21947684832 is a wasteful number, since it uses less digits than its factorization.

21947684832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1303 (or 1286 counting only the distinct ones).

The product of its digits is 4644864, while the sum is 54.

The spelling of 21947684832 in words is "twenty-one billion, nine hundred forty-seven million, six hundred eighty-four thousand, eight hundred thirty-two".