870321 has 4 divisors (see below), whose sum is σ = 1160432. Its totient is φ = 580212.

The previous prime is 870301. The next prime is 870323. The reversal of 870321 is 123078.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 870321 - 2⁹ = 869809 is a prime.

It is a D-number.

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

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 870321.

It is not an unprimeable number, because it can be changed into a prime (870323) 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, 145051 + ... + 145056.

It is an arithmetic number, because the mean of its divisors is an integer number (290108).

2⁸⁷⁰³²¹ is an apocalyptic number.

It is an amenable number.

870321 is a deficient number, since it is larger than the sum of its proper divisors (290111).

870321 is a wasteful number, since it uses less digits than its factorization.

870321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290110.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 870321 is about 932.9099635013. The cubic root of 870321 is about 95.4757666279.

Adding to 870321 its reverse (123078), we get a palindrome (993399).

The spelling of 870321 in words is "eight hundred seventy thousand, three hundred twenty-one".