21043232352 has 168 divisors, whose sum is σ = 62245781640. Its totient is φ = 6999644160.

The previous prime is 21043232321. The next prime is 21043232389. The reversal of 21043232352 is 25323234012.

21043232352 is a `hidden beast` number, since 2 + 104 + 323 + 235 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 21671227 + ... + 21672197.

It is an arithmetic number, because the mean of its divisors is an integer number (370510605).

Almost surely, 2^21043232352 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 21043232352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31122890820).

21043232352 is an abundant number, since it is smaller than the sum of its proper divisors (41202549288).

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

21043232352 is an frugal number, since it uses more digits than its factorization.

21043232352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1928 (or 1905 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 27.

Adding to 21043232352 its reverse (25323234012), we get a palindrome (46366466364).

The spelling of 21043232352 in words is "twenty-one billion, forty-three million, two hundred thirty-two thousand, three hundred fifty-two".