11855999 has 2 divisors, whose sum is σ = 11856000. Its totient is φ = 11855998.

The previous prime is 11855993. The next prime is 11856001. The reversal of 11855999 is 99955811.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11855999 - 2⁸ = 11855743 is a prime.

Together with 11856001, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11855993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5927999 + 5928000.

It is an arithmetic number, because the mean of its divisors is an integer number (5928000).

Almost surely, 2^11855999 is an apocalyptic number.

11855999 is a deficient number, since it is larger than the sum of its proper divisors (1).

11855999 is an equidigital number, since it uses as much as digits as its factorization.

11855999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 47.

The square root of 11855999 is about 3443.2541294537. The cubic root of 11855999 is about 228.0233830025.

The spelling of 11855999 in words is "eleven million, eight hundred fifty-five thousand, nine hundred ninety-nine".