11091999 has 8 divisors (see below), whose sum is σ = 15068592. Its totient is φ = 7255040.

The previous prime is 11091959. The next prime is 11092001. The reversal of 11091999 is 99919011.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11091999 - 2¹¹ = 11089951 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11091919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34722 + ... + 35039.

It is an arithmetic number, because the mean of its divisors is an integer number (1883574).

Almost surely, 2^11091999 is an apocalyptic number.

11091999 is a deficient number, since it is larger than the sum of its proper divisors (3976593).

11091999 is an equidigital number, since it uses as much as digits as its factorization.

11091999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69817.

The product of its (nonzero) digits is 6561, while the sum is 39.

The square root of 11091999 is about 3330.4652828096. The cubic root of 11091999 is about 223.0163004969.

It can be divided in two parts, 11091 and 999, that added together give a triangular number (12090 = T₁₅₅).

The spelling of 11091999 in words is "eleven million, ninety-one thousand, nine hundred ninety-nine".