21320313210 has 256 divisors, whose sum is σ = 66638868480. Its totient is φ = 4750099200.

The previous prime is 21320313187. The next prime is 21320313211. The reversal of 21320313210 is 1231302312.

21320313210 is a `hidden beast` number, since 21 + 320 + 3 + 1 + 321 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21320313211) 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 127 ways as a sum of consecutive naturals, for example, 12788797 + ... + 12790463.

It is an arithmetic number, because the mean of its divisors is an integer number (260308080).

Almost surely, 2^21320313210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21320313210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33319434240).

21320313210 is an abundant number, since it is smaller than the sum of its proper divisors (45318555270).

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

21320313210 is a wasteful number, since it uses less digits than its factorization.

21320313210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1858 (or 1852 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21320313210 its reverse (1231302312), we get a palindrome (22551615522).

The spelling of 21320313210 in words is "twenty-one billion, three hundred twenty million, three hundred thirteen thousand, two hundred ten".