13565440 has 80 divisors (see below), whose sum is σ = 37220832. Its totient is φ = 4644864.

The previous prime is 13565413. The next prime is 13565441. The reversal of 13565440 is 4456531.

13565440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 13565399 and 13565408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13565441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17542 + ... + 18298.

Almost surely, 2^13565440 is an apocalyptic number.

13565440 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 13565440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18610416).

13565440 is an abundant number, since it is smaller than the sum of its proper divisors (23655392).

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

13565440 is an frugal number, since it uses more digits than its factorization.

13565440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787 (or 771 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 13565440 is about 3683.1291044437. The cubic root of 13565440 is about 238.4942767827.

The spelling of 13565440 in words is "thirteen million, five hundred sixty-five thousand, four hundred forty".