21251303042240 has 112 divisors (see below), whose sum is σ = 50989903729920. Its totient is φ = 8435920051200.

The previous prime is 21251303042239. The next prime is 21251303042261. The reversal of 21251303042240 is 4224030315212.

21251303042240 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

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 15 ways as a sum of consecutive naturals, for example, 49022279 + ... + 49453881.

Almost surely, 2^{21251303042240} is an apocalyptic number.

21251303042240 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 21251303042240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25494951864960).

21251303042240 is an abundant number, since it is smaller than the sum of its proper divisors (29738600687680).

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

21251303042240 is a wasteful number, since it uses less digits than its factorization.

21251303042240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432790 (or 432780 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 29.

Adding to 21251303042240 its reverse (4224030315212), we get a palindrome (25475333357452).

The spelling of 21251303042240 in words is "twenty-one trillion, two hundred fifty-one billion, three hundred three million, forty-two thousand, two hundred forty".