21305240543040 has 56 divisors (see below), whose sum is σ = 67644138727200. Its totient is φ = 5681397477888.

The previous prime is 21305240543011. The next prime is 21305240543047. The reversal of 21305240543040 is 4034504250312.

It is a junction number, because it is equal to n+sod(n) for n = 21305240542992 and 21305240543010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21305240543047) 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 7 ways as a sum of consecutive naturals, for example, 11096478490 + ... + 11096480409.

It is an arithmetic number, because the mean of its divisors is an integer number (1207931048700).

Almost surely, 2^{21305240543040} is an apocalyptic number.

21305240543040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21305240543040 is an abundant number, since it is smaller than the sum of its proper divisors (46338898184160).

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

21305240543040 is a wasteful number, since it uses less digits than its factorization.

21305240543040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22192958919 (or 22192958909 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 33.

Adding to 21305240543040 its reverse (4034504250312), we get a palindrome (25339744793352).

The spelling of 21305240543040 in words is "twenty-one trillion, three hundred five billion, two hundred forty million, five hundred forty-three thousand, forty".