13718561 has 4 divisors (see below), whose sum is σ = 13725972. Its totient is φ = 13711152.

The previous prime is 13718531. The next prime is 13718563. The reversal of 13718561 is 16581731.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 16581731 = 73 ⋅227147.

It can be written as a sum of positive squares in 2 ways, for example, as 65536 + 13653025 = 256^2 + 3695^2 .

It is a cyclic number.

It is not a de Polignac number, because 13718561 - 2¹⁰ = 13717537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13718563) 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, 1715 + ... + 5511.

It is an arithmetic number, because the mean of its divisors is an integer number (3431493).

Almost surely, 2^13718561 is an apocalyptic number.

It is an amenable number.

13718561 is a deficient number, since it is larger than the sum of its proper divisors (7411).

13718561 is an equidigital number, since it uses as much as digits as its factorization.

13718561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7410.

The product of its digits is 5040, while the sum is 32.

The square root of 13718561 is about 3703.8575836552. The cubic root of 13718561 is about 239.3882626660.

The spelling of 13718561 in words is "thirteen million, seven hundred eighteen thousand, five hundred sixty-one".