21533454355500 has 288 divisors, whose sum is σ = 70554970624320. Its totient is φ = 5733439718400.

The previous prime is 21533454355397. The next prime is 21533454355541. The reversal of 21533454355500 is 555345433512.

21533454355500 is a `hidden beast` number, since 2 + 1 + 5 + 3 + 3 + 4 + 543 + 55 + 50 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 79203796 + ... + 79475204.

It is an arithmetic number, because the mean of its divisors is an integer number (244982536890).

Almost surely, 2^{21533454355500} is an apocalyptic number.

21533454355500 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 21533454355500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35277485312160).

21533454355500 is an abundant number, since it is smaller than the sum of its proper divisors (49021516268820).

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

21533454355500 is a wasteful number, since it uses less digits than its factorization.

21533454355500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272096 (or 272072 counting only the distinct ones).

The product of its (nonzero) digits is 2700000, while the sum is 45.

The spelling of 21533454355500 in words is "twenty-one trillion, five hundred thirty-three billion, four hundred fifty-four million, three hundred fifty-five thousand, five hundred".