21310015320 has 192 divisors, whose sum is σ = 77596215840. Its totient is φ = 5026406400.

The previous prime is 21310015297. The next prime is 21310015367. The reversal of 21310015320 is 2351001312.

21310015320 is a `hidden beast` number, since 2 + 131 + 0 + 0 + 1 + 532 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 21310015293 and 21310015302.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 73800 + ... + 219240.

Almost surely, 2^21310015320 is an apocalyptic number.

21310015320 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 21310015320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38798107920).

21310015320 is an abundant number, since it is smaller than the sum of its proper divisors (56286200520).

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

21310015320 is a wasteful number, since it uses less digits than its factorization.

21310015320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145506 (or 145499 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

Adding to 21310015320 its reverse (2351001312), we get a palindrome (23661016632).

The spelling of 21310015320 in words is "twenty-one billion, three hundred ten million, fifteen thousand, three hundred twenty".