13221020320 has 48 divisors (see below), whose sum is σ = 31444345800. Its totient is φ = 5252905984.

The previous prime is 13221020311. The next prime is 13221020341. The reversal of 13221020320 is 2302012231.

It can be written as a sum of positive squares in 4 ways, for example, as 6543515664 + 6677504656 = 80892^2 + 81716^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 13221020294 and 13221020303.

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, 253447 + ... + 301126.

Almost surely, 2^13221020320 is an apocalyptic number.

13221020320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13221020320 is an abundant number, since it is smaller than the sum of its proper divisors (18223325480).

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

13221020320 is a wasteful number, since it uses less digits than its factorization.

13221020320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554737 (or 554729 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 13221020320 its reverse (2302012231), we get a palindrome (15523032551).

The spelling of 13221020320 in words is "thirteen billion, two hundred twenty-one million, twenty thousand, three hundred twenty".