11891871 has 6 divisors (see below), whose sum is σ = 17177160. Its totient is φ = 7927908.

The previous prime is 11891833. The next prime is 11891917. The reversal of 11891871 is 17819811.

It is a happy number.

It is not a de Polignac number, because 11891871 - 2¹³ = 11883679 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11891801) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 660651 + ... + 660668.

It is an arithmetic number, because the mean of its divisors is an integer number (2862860).

Almost surely, 2^11891871 is an apocalyptic number.

11891871 is a deficient number, since it is larger than the sum of its proper divisors (5285289).

11891871 is a wasteful number, since it uses less digits than its factorization.

11891871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1321325 (or 1321322 counting only the distinct ones).

The product of its digits is 4032, while the sum is 36.

The square root of 11891871 is about 3448.4592211595. The cubic root of 11891871 is about 228.2531237738.

The spelling of 11891871 in words is "eleven million, eight hundred ninety-one thousand, eight hundred seventy-one".