21320310016 has 72 divisors (see below), whose sum is σ = 45445478400. Its totient is φ = 9960437760.

The previous prime is 21320309981. The next prime is 21320310017. The reversal of 21320310016 is 61001302312.

It is a junction number, because it is equal to n+sod(n) for n = 21320309975 and 21320310002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320310017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183825 + ... + 276463.

It is an arithmetic number, because the mean of its divisors is an integer number (631187200).

Almost surely, 2^21320310016 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21320310016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22722739200).

21320310016 is an abundant number, since it is smaller than the sum of its proper divisors (24125168384).

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

21320310016 is an equidigital number, since it uses as much as digits as its factorization.

21320310016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92715 (or 92701 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21320310016 its reverse (61001302312), we get a palindrome (82321612328).

The spelling of 21320310016 in words is "twenty-one billion, three hundred twenty million, three hundred ten thousand, sixteen".