21533322240 has 264 divisors, whose sum is σ = 74922951168. Its totient is φ = 5718343680.

The previous prime is 21533322227. The next prime is 21533322257. The reversal of 21533322240 is 4222333512.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 12947649 + ... + 12949311.

Almost surely, 2^21533322240 is an apocalyptic number.

21533322240 is a gapful number since it is divisible by the number (20) 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 21533322240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37461475584).

21533322240 is an abundant number, since it is smaller than the sum of its proper divisors (53389628928).

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

21533322240 is a wasteful number, since it uses less digits than its factorization.

21533322240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1975 (or 1954 counting only the distinct ones).

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

Adding to 21533322240 its reverse (4222333512), we get a palindrome (25755655752).

The spelling of 21533322240 in words is "twenty-one billion, five hundred thirty-three million, three hundred twenty-two thousand, two hundred forty".