810440 has 16 divisors (see below), whose sum is σ = 1823580. Its totient is φ = 324160.

The previous prime is 810437. The next prime is 810443. The reversal of 810440 is 44018.

It is a happy number.

810440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (810437) and next prime (810443).

It can be written as a sum of positive squares in 2 ways, for example, as 682276 + 128164 = 826^2 + 358^2 .

It is not an unprimeable number, because it can be changed into a prime (810443) 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, 10091 + ... + 10170.

2⁸¹⁰⁴⁴⁰ is an apocalyptic number.

It is an amenable number.

810440 is an abundant number, since it is smaller than the sum of its proper divisors (1013140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

810440 is a wasteful number, since it uses less digits than its factorization.

810440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20272 (or 20268 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 810440 is about 900.2444112573. The cubic root of 810440 is about 93.2338509172.

Adding to 810440 its reverse (44018), we get a palindrome (854458).

The spelling of 810440 in words is "eight hundred ten thousand, four hundred forty".