13243520 has 32 divisors (see below), whose sum is σ = 31661820. Its totient is φ = 5297152.

The previous prime is 13243471. The next prime is 13243537. The reversal of 13243520 is 2534231.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12902464 + 341056 = 3592^2 + 584^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 13243492 and 13243501.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9707 + ... + 10986.

Almost surely, 2^13243520 is an apocalyptic number.

13243520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13243520 is an abundant number, since it is smaller than the sum of its proper divisors (18418300).

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

13243520 is an equidigital number, since it uses as much as digits as its factorization.

13243520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20712 (or 20700 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 13243520 is about 3639.1647393324. The cubic root of 13243520 is about 236.5925929218.

Adding to 13243520 its reverse (2534231), we get a palindrome (15777751).

The spelling of 13243520 in words is "thirteen million, two hundred forty-three thousand, five hundred twenty".