13521313220 has 48 divisors (see below), whose sum is σ = 29424170160. Its totient is φ = 5213085696.

The previous prime is 13521313217. The next prime is 13521313243. The reversal of 13521313220 is 2231312531.

It can be written as a sum of positive squares in 8 ways, for example, as 63457156 + 13457856064 = 7966^2 + 116008^2 .

It is a super-2 number, since 2×13521313220² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 324284 + ... + 363596.

It is an arithmetic number, because the mean of its divisors is an integer number (613003545).

Almost surely, 2^13521313220 is an apocalyptic number.

13521313220 is a gapful number since it is divisible by the number (10) 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 13521313220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14712085080).

13521313220 is an abundant number, since it is smaller than the sum of its proper divisors (15902856940).

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

13521313220 is a wasteful number, since it uses less digits than its factorization.

13521313220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39944 (or 39942 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 23.

Adding to 13521313220 its reverse (2231312531), we get a palindrome (15752625751).

The spelling of 13521313220 in words is "thirteen billion, five hundred twenty-one million, three hundred thirteen thousand, two hundred twenty".