878321 has 4 divisors (see below), whose sum is σ = 883572. Its totient is φ = 873072.

The previous prime is 878309. The next prime is 878359. The reversal of 878321 is 123878.

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

It can be written as a sum of positive squares in 2 ways, for example, as 829921 + 48400 = 911^2 + 220^2 .

It is a cyclic number.

It is not a de Polignac number, because 878321 - 2¹⁰ = 877297 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (878021) 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, 2366 + ... + 2711.

It is an arithmetic number, because the mean of its divisors is an integer number (220893).

2⁸⁷⁸³²¹ is an apocalyptic number.

It is an amenable number.

878321 is a deficient number, since it is larger than the sum of its proper divisors (5251).

878321 is a wasteful number, since it uses less digits than its factorization.

878321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5250.

The product of its digits is 2688, while the sum is 29.

The square root of 878321 is about 937.1878146882. The cubic root of 878321 is about 95.7674129311.

The spelling of 878321 in words is "eight hundred seventy-eight thousand, three hundred twenty-one".