827991 has 12 divisors (see below), whose sum is σ = 1204632. Its totient is φ = 548016.

The previous prime is 827989. The next prime is 828007. The reversal of 827991 is 199728.

It is a happy number.

827991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 827991 - 2¹ = 827989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (827941) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1540 + ... + 2006.

It is an arithmetic number, because the mean of its divisors is an integer number (100386).

2⁸²⁷⁹⁹¹ is an apocalyptic number.

827991 is a deficient number, since it is larger than the sum of its proper divisors (376641).

827991 is a wasteful number, since it uses less digits than its factorization.

827991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670 (or 667 counting only the distinct ones).

The product of its digits is 9072, while the sum is 36.

The square root of 827991 is about 909.9401079192. The cubic root of 827991 is about 93.9020785026.

The spelling of 827991 in words is "eight hundred twenty-seven thousand, nine hundred ninety-one".