11171999 has 4 divisors (see below), whose sum is σ = 11180064. Its totient is φ = 11163936.

The previous prime is 11171987. The next prime is 11172001. The reversal of 11171999 is 99917111.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 99917111 = 7 ⋅14273873.

It is a cyclic number.

It is not a de Polignac number, because 11171999 - 2²⁰ = 10123423 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 (11171929) 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, 1367 + ... + 4920.

It is an arithmetic number, because the mean of its divisors is an integer number (2795016).

Almost surely, 2^11171999 is an apocalyptic number.

11171999 is a deficient number, since it is larger than the sum of its proper divisors (8065).

11171999 is an equidigital number, since it uses as much as digits as its factorization.

11171999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8064.

The product of its digits is 5103, while the sum is 38.

The square root of 11171999 is about 3342.4540385770. The cubic root of 11171999 is about 223.5511779997.

The spelling of 11171999 in words is "eleven million, one hundred seventy-one thousand, nine hundred ninety-nine".