21321310530 has 32 divisors (see below), whose sum is σ = 55107388224. Its totient is φ = 5248322496.

The previous prime is 21321310519. The next prime is 21321310537. The reversal of 21321310530 is 3501312312.

It is a junction number, because it is equal to n+sod(n) for n = 21321310497 and 21321310506.

It is not an unprimeable number, because it can be changed into a prime (21321310537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27334624 + ... + 27335403.

It is an arithmetic number, because the mean of its divisors is an integer number (1722105882).

Almost surely, 2^21321310530 is an apocalyptic number.

21321310530 is an abundant number, since it is smaller than the sum of its proper divisors (33786077694).

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

21321310530 is a wasteful number, since it uses less digits than its factorization.

21321310530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54670050.

The product of its (nonzero) digits is 540, while the sum is 21.

Adding to 21321310530 its reverse (3501312312), we get a palindrome (24822622842).

The spelling of 21321310530 in words is "twenty-one billion, three hundred twenty-one million, three hundred ten thousand, five hundred thirty".