11993281 has 4 divisors (see below), whose sum is σ = 12514752. Its totient is φ = 11471812.

The previous prime is 11993273. The next prime is 11993287. The reversal of 11993281 is 18239911.

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: 18239911 = 769 ⋅23719.

It is a cyclic number.

It is not a de Polignac number, because 11993281 - 2³ = 11993273 is a prime.

It is a super-2 number, since 2×11993281² = 287677578289922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11993287) 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, 260701 + ... + 260746.

It is an arithmetic number, because the mean of its divisors is an integer number (3128688).

Almost surely, 2^11993281 is an apocalyptic number.

It is an amenable number.

11993281 is a deficient number, since it is larger than the sum of its proper divisors (521471).

11993281 is an equidigital number, since it uses as much as digits as its factorization.

11993281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521470.

The product of its digits is 3888, while the sum is 34.

The square root of 11993281 is about 3463.1316752327. The cubic root of 11993281 is about 228.9001108943.

The spelling of 11993281 in words is "eleven million, nine hundred ninety-three thousand, two hundred eighty-one".