820870 has 32 divisors (see below), whose sum is σ = 1596672. Its totient is φ = 303072.

The previous prime is 820837. The next prime is 820873. The reversal of 820870 is 78028.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820873) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9849 + ... + 9931.

It is an arithmetic number, because the mean of its divisors is an integer number (49896).

2⁸²⁰⁸⁷⁰ is an apocalyptic number.

820870 is a deficient number, since it is larger than the sum of its proper divisors (775802).

820870 is a wasteful number, since it uses less digits than its factorization.

820870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 820870 is about 906.0187636026. The cubic root of 820870 is about 93.6321066226.

Adding to 820870 its reverse (78028), we get a palindrome (898898).

The spelling of 820870 in words is "eight hundred twenty thousand, eight hundred seventy".