11471991 has 16 divisors (see below), whose sum is σ = 17049600. Its totient is φ = 6818688.

The previous prime is 11471989. The next prime is 11472031. The reversal of 11471991 is 19917411.

It is not a de Polignac number, because 11471991 - 2¹ = 11471989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11471191) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4951 + ... + 6888.

It is an arithmetic number, because the mean of its divisors is an integer number (1065600).

Almost surely, 2^11471991 is an apocalyptic number.

11471991 is a deficient number, since it is larger than the sum of its proper divisors (5577609).

11471991 is a wasteful number, since it uses less digits than its factorization.

11471991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11878.

The product of its digits is 2268, while the sum is 33.

The square root of 11471991 is about 3387.0327722064. The cubic root of 11471991 is about 225.5344726003.

The spelling of 11471991 in words is "eleven million, four hundred seventy-one thousand, nine hundred ninety-one".