11981199 has 4 divisors (see below), whose sum is σ = 15974936. Its totient is φ = 7987464.

The previous prime is 11981197. The next prime is 11981201. The reversal of 11981199 is 99118911.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (11981197) and next prime (11981201).

It is not a de Polignac number, because 11981199 - 2¹ = 11981197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11981197) 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, 1996864 + ... + 1996869.

It is an arithmetic number, because the mean of its divisors is an integer number (3993734).

Almost surely, 2^11981199 is an apocalyptic number.

11981199 is a deficient number, since it is larger than the sum of its proper divisors (3993737).

11981199 is an equidigital number, since it uses as much as digits as its factorization.

11981199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3993736.

The product of its digits is 5832, while the sum is 39.

The square root of 11981199 is about 3461.3868607828. The cubic root of 11981199 is about 228.8232206106.

It can be divided in two parts, 119 and 81199, that added together give a palindrome (81318).

The spelling of 11981199 in words is "eleven million, nine hundred eighty-one thousand, one hundred ninety-nine".