21131324581752 has 1536 divisors, whose sum is σ = 79373758464000. Its totient is φ = 5107062804480.

The previous prime is 21131324581733. The next prime is 21131324581811. The reversal of 21131324581752 is 25718542313112.

21131324581752 is a `hidden beast` number, since 2 + 1 + 1 + 3 + 13 + 2 + 4 + 581 + 7 + 52 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21131324581698 and 21131324581707.

It is a congruent number.

It is an unprimeable number.

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 383 ways as a sum of consecutive naturals, for example, 14746213228 + ... + 14746214660.

It is an arithmetic number, because the mean of its divisors is an integer number (51675624000).

Almost surely, 2^{21131324581752} is an apocalyptic number.

21131324581752 is a gapful number since it is divisible by the number (22) 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 21131324581752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39686879232000).

21131324581752 is an abundant number, since it is smaller than the sum of its proper divisors (58242433882248).

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

21131324581752 is a wasteful number, since it uses less digits than its factorization.

21131324581752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1623 (or 1607 counting only the distinct ones).

The product of its digits is 403200, while the sum is 45.

Adding to 21131324581752 its reverse (25718542313112), we get a palindrome (46849866894864).

The spelling of 21131324581752 in words is "twenty-one trillion, one hundred thirty-one billion, three hundred twenty-four million, five hundred eighty-one thousand, seven hundred fifty-two".