21210131320 has 32 divisors (see below), whose sum is σ = 54540338400. Its totient is φ = 7272044928.

The previous prime is 21210131317. The next prime is 21210131353. The reversal of 21210131320 is 2313101212.

It is a super-2 number, since 2×21210131320² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21210131294 and 21210131303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37874955 + ... + 37875514.

It is an arithmetic number, because the mean of its divisors is an integer number (1704385575).

Almost surely, 2^21210131320 is an apocalyptic number.

21210131320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210131320 is an abundant number, since it is smaller than the sum of its proper divisors (33330207080).

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

21210131320 is a wasteful number, since it uses less digits than its factorization.

21210131320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75750487 (or 75750483 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21210131320 its reverse (2313101212), we get a palindrome (23523232532).

The spelling of 21210131320 in words is "twenty-one billion, two hundred ten million, one hundred thirty-one thousand, three hundred twenty".