11681281 has 4 divisors (see below), whose sum is σ = 11711700. Its totient is φ = 11650864.

The previous prime is 11681273. The next prime is 11681291. The reversal of 11681281 is 18218611.

11681281 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18218611 = 17 ⋅1071683.

It can be written as a sum of positive squares in 2 ways, for example, as 8071281 + 3610000 = 2841^2 + 1900^2 .

It is a cyclic number.

It is not a de Polignac number, because 11681281 - 2³ = 11681273 is a prime.

It is a super-2 number, since 2×11681281² = 272904651601922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11681221) 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, 14626 + ... + 15403.

It is an arithmetic number, because the mean of its divisors is an integer number (2927925).

Almost surely, 2^11681281 is an apocalyptic number.

It is an amenable number.

11681281 is a deficient number, since it is larger than the sum of its proper divisors (30419).

11681281 is an equidigital number, since it uses as much as digits as its factorization.

11681281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30418.

The product of its digits is 768, while the sum is 28.

The square root of 11681281 is about 3417.7889051257. The cubic root of 11681281 is about 226.8977331783.

Adding to 11681281 its reverse (18218611), we get a palindrome (29899892).

The spelling of 11681281 in words is "eleven million, six hundred eighty-one thousand, two hundred eighty-one".