21240237388680 has 512 divisors, whose sum is σ = 75854444544000. Its totient is φ = 5276982574080.

The previous prime is 21240237388663. The next prime is 21240237388703. The reversal of 21240237388680 is 8688373204212.

21240237388680 is a `hidden beast` number, since 2 + 1 + 24 + 0 + 237 + 388 + 6 + 8 + 0 = 666.

It is a super-2 number, since 2×21240237388680² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 104413227 + ... + 104616453.

It is an arithmetic number, because the mean of its divisors is an integer number (148153212000).

Almost surely, 2^{21240237388680} is an apocalyptic number.

21240237388680 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 21240237388680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37927222272000).

21240237388680 is an abundant number, since it is smaller than the sum of its proper divisors (54614207155320).

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

21240237388680 is a wasteful number, since it uses less digits than its factorization.

21240237388680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203394 (or 203384 counting only the distinct ones).

The product of its (nonzero) digits is 6193152, while the sum is 54.

The spelling of 21240237388680 in words is "twenty-one trillion, two hundred forty billion, two hundred thirty-seven million, three hundred eighty-eight thousand, six hundred eighty".