861785140 has 12 divisors (see below), whose sum is σ = 1809748836. Its totient is φ = 344714048.

The previous prime is 861785101. The next prime is 861785161. The reversal of 861785140 is 41587168.

It can be written as a sum of positive squares in 2 ways, for example, as 307371024 + 554414116 = 17532^2 + 23546^2 .

It is a junction number, because it is equal to n+sod(n) for n = 861785093 and 861785102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21544609 + ... + 21544648.

It is an arithmetic number, because the mean of its divisors is an integer number (150812403).

Almost surely, 2^861785140 is an apocalyptic number.

It is an amenable number.

861785140 is an abundant number, since it is smaller than the sum of its proper divisors (947963696).

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

861785140 is a wasteful number, since it uses less digits than its factorization.

861785140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43089266 (or 43089264 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 40.

The square root of 861785140 is about 29356.1772034439. The cubic root of 861785140 is about 951.6260756980.

The spelling of 861785140 in words is "eight hundred sixty-one million, seven hundred eighty-five thousand, one hundred forty".