11888991 has 8 divisors (see below), whose sum is σ = 17613360. Its totient is φ = 7925976.

The previous prime is 11888983. The next prime is 11889011. The reversal of 11888991 is 19988811.

It is not a de Polignac number, because 11888991 - 2³ = 11888983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11888971) 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, 220140 + ... + 220193.

It is an arithmetic number, because the mean of its divisors is an integer number (2201670).

Almost surely, 2^11888991 is an apocalyptic number.

11888991 is a deficient number, since it is larger than the sum of its proper divisors (5724369).

11888991 is an equidigital number, since it uses as much as digits as its factorization.

11888991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440342 (or 440336 counting only the distinct ones).

The product of its digits is 41472, while the sum is 45.

The square root of 11888991 is about 3448.0416180783. The cubic root of 11888991 is about 228.2346960016.

The spelling of 11888991 in words is "eleven million, eight hundred eighty-eight thousand, nine hundred ninety-one".