21535232304 has 160 divisors (see below), whose sum is σ = 59640182784. Its totient is φ = 6680171520.

The previous prime is 21535232297. The next prime is 21535232309. The reversal of 21535232304 is 40323253512.

It is not an unprimeable number, because it can be changed into a prime (21535232309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9390582 + ... + 9392874.

Almost surely, 2^21535232304 is an apocalyptic number.

21535232304 is a gapful number since it is divisible by the number (24) 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 21535232304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29820091392).

21535232304 is an abundant number, since it is smaller than the sum of its proper divisors (38104950480).

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

21535232304 is a wasteful number, since it uses less digits than its factorization.

21535232304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2555 (or 2549 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 30.

Adding to 21535232304 its reverse (40323253512), we get a palindrome (61858485816).

The spelling of 21535232304 in words is "twenty-one billion, five hundred thirty-five million, two hundred thirty-two thousand, three hundred four".