11855971 has 4 divisors (see below), whose sum is σ = 12371472. Its totient is φ = 11340472.

The previous prime is 11855959. The next prime is 11855989. The reversal of 11855971 is 17955811.

11855971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17955811 = 43 ⋅417577.

It is not a de Polignac number, because 11855971 - 2¹⁷ = 11724899 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11855971.

It is not an unprimeable number, because it can be changed into a prime (11855911) 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, 257716 + ... + 257761.

It is an arithmetic number, because the mean of its divisors is an integer number (3092868).

Almost surely, 2^11855971 is an apocalyptic number.

11855971 is a deficient number, since it is larger than the sum of its proper divisors (515501).

11855971 is an equidigital number, since it uses as much as digits as its factorization.

11855971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515500.

The product of its digits is 12600, while the sum is 37.

The square root of 11855971 is about 3443.2500635301. The cubic root of 11855971 is about 228.0232034967.

The spelling of 11855971 in words is "eleven million, eight hundred fifty-five thousand, nine hundred seventy-one".