13404240 has 60 divisors (see below), whose sum is σ = 45018324. Its totient is φ = 3574272.

The previous prime is 13404233. The next prime is 13404241. The reversal of 13404240 is 4240431.

It can be written as a sum of positive squares in 2 ways, for example, as 9809424 + 3594816 = 3132^2 + 1896^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13404241) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8589 + ... + 10028.

Almost surely, 2^13404240 is an apocalyptic number.

13404240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13404240 is an abundant number, since it is smaller than the sum of its proper divisors (31614084).

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

13404240 is a wasteful number, since it uses less digits than its factorization.

13404240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18636 (or 18627 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 13404240 is about 3661.1801376059. The cubic root of 13404240 is about 237.5458231066.

Adding to 13404240 its reverse (4240431), we get a palindrome (17644671).

The spelling of 13404240 in words is "thirteen million, four hundred four thousand, two hundred forty".