828391 has 4 divisors (see below), whose sum is σ = 864432. Its totient is φ = 792352.

The previous prime is 828383. The next prime is 828397. The reversal of 828391 is 193828.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 828391 - 2³ = 828383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (828397) 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, 17986 + ... + 18031.

It is an arithmetic number, because the mean of its divisors is an integer number (216108).

2⁸²⁸³⁹¹ is an apocalyptic number.

828391 is a deficient number, since it is larger than the sum of its proper divisors (36041).

828391 is a wasteful number, since it uses less digits than its factorization.

828391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36040.

The product of its digits is 3456, while the sum is 31.

The square root of 828391 is about 910.1598760657. The cubic root of 828391 is about 93.9171973403.

The spelling of 828391 in words is "eight hundred twenty-eight thousand, three hundred ninety-one".