21340043560 has 256 divisors, whose sum is σ = 57297300480. Its totient is φ = 7065600000.

The previous prime is 21340043539. The next prime is 21340043561. The reversal of 21340043560 is 6534004312.

It is not an unprimeable number, because it can be changed into a prime (21340043561) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 35507260 + ... + 35507860.

It is an arithmetic number, because the mean of its divisors is an integer number (223817580).

Almost surely, 2^21340043560 is an apocalyptic number.

21340043560 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 21340043560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28648650240).

21340043560 is an abundant number, since it is smaller than the sum of its proper divisors (35957256920).

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

21340043560 is a wasteful number, since it uses less digits than its factorization.

21340043560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 788 (or 784 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 28.

Adding to 21340043560 its reverse (6534004312), we get a palindrome (27874047872).

The spelling of 21340043560 in words is "twenty-one billion, three hundred forty million, forty-three thousand, five hundred sixty".