11131565 has 4 divisors (see below), whose sum is σ = 13357884. Its totient is φ = 8905248.

The previous prime is 11131559. The next prime is 11131567. The reversal of 11131565 is 56513111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56513111 = 577 ⋅97943.

It can be written as a sum of positive squares in 2 ways, for example, as 7123561 + 4008004 = 2669^2 + 2002^2 .

It is a cyclic number.

It is not a de Polignac number, because 11131565 - 2⁶ = 11131501 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11131565.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11131567) 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, 1113152 + ... + 1113161.

It is an arithmetic number, because the mean of its divisors is an integer number (3339471).

Almost surely, 2^11131565 is an apocalyptic number.

It is an amenable number.

11131565 is a deficient number, since it is larger than the sum of its proper divisors (2226319).

11131565 is an equidigital number, since it uses as much as digits as its factorization.

11131565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2226318.

The product of its digits is 450, while the sum is 23.

The square root of 11131565 is about 3336.4000059945. The cubic root of 11131565 is about 223.2811578322.

Adding to 11131565 its reverse (56513111), we get a palindrome (67644676).

The spelling of 11131565 in words is "eleven million, one hundred thirty-one thousand, five hundred sixty-five".