823139 has 4 divisors (see below), whose sum is σ = 845424. Its totient is φ = 800856.

The previous prime is 823129. The next prime is 823153. The reversal of 823139 is 931328.

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 823139 - 2⁸ = 822883 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (823129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11087 + ... + 11160.

It is an arithmetic number, because the mean of its divisors is an integer number (211356).

2⁸²³¹³⁹ is an apocalyptic number.

823139 is a deficient number, since it is larger than the sum of its proper divisors (22285).

823139 is a wasteful number, since it uses less digits than its factorization.

823139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22284.

The product of its digits is 1296, while the sum is 26.

The square root of 823139 is about 907.2700810674. The cubic root of 823139 is about 93.7182980218.

The spelling of 823139 in words is "eight hundred twenty-three thousand, one hundred thirty-nine".