13523240 has 32 divisors (see below), whose sum is σ = 30645000. Its totient is φ = 5370624.

The previous prime is 13523239. The next prime is 13523243. The reversal of 13523240 is 4232531.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4318084 + 9205156 = 2078^2 + 3034^2 .

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

It is not an unprimeable number, because it can be changed into a prime (13523243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4826 + ... + 7094.

Almost surely, 2^13523240 is an apocalyptic number.

13523240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13523240 is an abundant number, since it is smaller than the sum of its proper divisors (17121760).

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

13523240 is a wasteful number, since it uses less digits than its factorization.

13523240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2429 (or 2425 counting only the distinct ones).

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

The square root of 13523240 is about 3677.3958176949. The cubic root of 13523240 is about 238.2467135415.

Adding to 13523240 its reverse (4232531), we get a palindrome (17755771).

The spelling of 13523240 in words is "thirteen million, five hundred twenty-three thousand, two hundred forty".