21555222115024 has 80 divisors (see below), whose sum is σ = 45170360318160. Its totient is φ = 9905542225920.

The previous prime is 21555222115013. The next prime is 21555222115033. The reversal of 21555222115024 is 42051122255512.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 43547342400 + 21511674772624 = 208680^2 + 4638068^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 310608522 + ... + 310677910.

It is an arithmetic number, because the mean of its divisors is an integer number (564629503977).

Almost surely, 2^{21555222115024} 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 21555222115024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22585180159080).

21555222115024 is an abundant number, since it is smaller than the sum of its proper divisors (23615138203136).

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

21555222115024 is a wasteful number, since it uses less digits than its factorization.

21555222115024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75848 (or 75842 counting only the distinct ones).

The product of its (nonzero) digits is 80000, while the sum is 37.

The spelling of 21555222115024 in words is "twenty-one trillion, five hundred fifty-five billion, two hundred twenty-two million, one hundred fifteen thousand, twenty-four".