11399881 has 4 divisors (see below), whose sum is σ = 11895552. Its totient is φ = 10904212.

The previous prime is 11399879. The next prime is 11399891. The reversal of 11399881 is 18899311.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 11399881 - 2¹ = 11399879 is a prime.

It is a super-2 number, since 2×11399881² = 259914573628322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11399891) 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, 247801 + ... + 247846.

It is an arithmetic number, because the mean of its divisors is an integer number (2973888).

Almost surely, 2^11399881 is an apocalyptic number.

It is an amenable number.

11399881 is a deficient number, since it is larger than the sum of its proper divisors (495671).

11399881 is an equidigital number, since it uses as much as digits as its factorization.

11399881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495670.

The product of its digits is 15552, while the sum is 40.

The square root of 11399881 is about 3376.3709808017. The cubic root of 11399881 is about 225.0609283555.

The spelling of 11399881 in words is "eleven million, three hundred ninety-nine thousand, eight hundred eighty-one".