861131428 has 12 divisors (see below), whose sum is σ = 1509632460. Its totient is φ = 429807872.

The previous prime is 861131417. The next prime is 861131429. The reversal of 861131428 is 824131168.

861131428 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 373958244 + 487173184 = 19338^2 + 22072^2 .

It is a junction number, because it is equal to n+sod(n) for n = 861131393 and 861131402.

It is not an unprimeable number, because it can be changed into a prime (861131429) 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, 186901 + ... + 191452.

It is an arithmetic number, because the mean of its divisors is an integer number (125802705).

Almost surely, 2^861131428 is an apocalyptic number.

It is an amenable number.

861131428 is a deficient number, since it is larger than the sum of its proper divisors (648501032).

861131428 is a wasteful number, since it uses less digits than its factorization.

861131428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378926 (or 378924 counting only the distinct ones).

The product of its digits is 9216, while the sum is 34.

The square root of 861131428 is about 29345.0409439142. The cubic root of 861131428 is about 951.3853943807.

The spelling of 861131428 in words is "eight hundred sixty-one million, one hundred thirty-one thousand, four hundred twenty-eight".