11165681 has 4 divisors (see below), whose sum is σ = 11425392. Its totient is φ = 10905972.

The previous prime is 11165677. The next prime is 11165689. The reversal of 11165681 is 18656111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18656111 = 457 ⋅40823.

It is a cyclic number.

It is not a de Polignac number, because 11165681 - 2² = 11165677 is a prime.

It is a super-2 number, since 2×11165681² = 249344864387522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11165689) 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, 129791 + ... + 129876.

It is an arithmetic number, because the mean of its divisors is an integer number (2856348).

Almost surely, 2^11165681 is an apocalyptic number.

It is an amenable number.

11165681 is a deficient number, since it is larger than the sum of its proper divisors (259711).

11165681 is an equidigital number, since it uses as much as digits as its factorization.

11165681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259710.

The product of its digits is 1440, while the sum is 29.

The square root of 11165681 is about 3341.5087909506. The cubic root of 11165681 is about 223.5090290917.

The spelling of 11165681 in words is "eleven million, one hundred sixty-five thousand, six hundred eighty-one".