815140 has 24 divisors (see below), whose sum is σ = 1746360. Its totient is φ = 319488.

The previous prime is 815123. The next prime is 815141. The reversal of 815140 is 41518.

It can be written as a sum of positive squares in 4 ways, for example, as 112896 + 702244 = 336^2 + 838^2 .

It is not an unprimeable number, because it can be changed into a prime (815141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 676 + ... + 1444.

It is an arithmetic number, because the mean of its divisors is an integer number (72765).

2⁸¹⁵¹⁴⁰ is an apocalyptic number.

It is an amenable number.

815140 is an abundant number, since it is smaller than the sum of its proper divisors (931220).

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

815140 is a wasteful number, since it uses less digits than its factorization.

815140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 831 (or 829 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 815140 is about 902.8510397624. The cubic root of 815140 is about 93.4137345740.

Adding to 815140 its reverse (41518), we get a palindrome (856658).

The spelling of 815140 in words is "eight hundred fifteen thousand, one hundred forty".