881991 has 24 divisors (see below), whose sum is σ = 1422720. Its totient is φ = 522000.

The previous prime is 881987. The next prime is 882017. The reversal of 881991 is 199188.

It is not a de Polignac number, because 881991 - 2² = 881987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (881911) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5766 + ... + 5916.

It is an arithmetic number, because the mean of its divisors is an integer number (59280).

2⁸⁸¹⁹⁹¹ is an apocalyptic number.

881991 is a deficient number, since it is larger than the sum of its proper divisors (540729).

881991 is a wasteful number, since it uses less digits than its factorization.

881991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227 (or 224 counting only the distinct ones).

The product of its digits is 5184, while the sum is 36.

The square root of 881991 is about 939.1437589635. The cubic root of 881991 is about 95.9006132884.

The spelling of 881991 in words is "eight hundred eighty-one thousand, nine hundred ninety-one".