21810751144728 has 256 divisors, whose sum is σ = 67817385216000. Its totient is φ = 5691824087040.

The previous prime is 21810751144709. The next prime is 21810751144729. The reversal of 21810751144728 is 82744115701812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21810751144729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 147754638 + ... + 147902178.

It is an arithmetic number, because the mean of its divisors is an integer number (264911661000).

Almost surely, 2^{21810751144728} is an apocalyptic number.

21810751144728 is a gapful number since it is divisible by the number (28) 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 21810751144728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33908692608000).

21810751144728 is an abundant number, since it is smaller than the sum of its proper divisors (46006634071272).

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

21810751144728 is a wasteful number, since it uses less digits than its factorization.

21810751144728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148282 (or 148278 counting only the distinct ones).

The product of its (nonzero) digits is 1003520, while the sum is 51.

The spelling of 21810751144728 in words is "twenty-one trillion, eight hundred ten billion, seven hundred fifty-one million, one hundred forty-four thousand, seven hundred twenty-eight".