13281220 has 12 divisors (see below), whose sum is σ = 27890604. Its totient is φ = 5312480.

The previous prime is 13281193. The next prime is 13281221. The reversal of 13281220 is 2218231.

13281220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 2005056 + 11276164 = 1416^2 + 3358^2 .

It is not an unprimeable number, because it can be changed into a prime (13281221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 332011 + ... + 332050.

It is an arithmetic number, because the mean of its divisors is an integer number (2324217).

Almost surely, 2^13281220 is an apocalyptic number.

13281220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13281220 is an abundant number, since it is smaller than the sum of its proper divisors (14609384).

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

13281220 is a wasteful number, since it uses less digits than its factorization.

13281220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 664070 (or 664068 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 13281220 is about 3644.3408183099. The cubic root of 13281220 is about 236.8168809870.

Adding to 13281220 its reverse (2218231), we get a palindrome (15499451).

The spelling of 13281220 in words is "thirteen million, two hundred eighty-one thousand, two hundred twenty".