831400840 has 32 divisors (see below), whose sum is σ = 1871527680. Its totient is φ = 332404672.

The previous prime is 831400831. The next prime is 831400847. The reversal of 831400840 is 48004138.

It is a junction number, because it is equal to n+sod(n) for n = 831400799 and 831400808.

It is not an unprimeable number, because it can be changed into a prime (831400847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123399 + ... + 129961.

It is an arithmetic number, because the mean of its divisors is an integer number (58485240).

Almost surely, 2^831400840 is an apocalyptic number.

It is an amenable number.

831400840 is an abundant number, since it is smaller than the sum of its proper divisors (1040126840).

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

831400840 is a wasteful number, since it uses less digits than its factorization.

831400840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9741 (or 9737 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 831400840 is about 28834.0222653726. The cubic root of 831400840 is about 940.3080475222.

Adding to 831400840 its reverse (48004138), we get a palindrome (879404978).

The spelling of 831400840 in words is "eight hundred thirty-one million, four hundred thousand, eight hundred forty".