861856078200 has 384 divisors, whose sum is σ = 3005507635200. Its totient is φ = 202713477120.

The previous prime is 861856078157. The next prime is 861856078211. The reversal of 861856078200 is 2870658168.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 231244737 + ... + 231248463.

It is an arithmetic number, because the mean of its divisors is an integer number (7826842800).

Almost surely, 2^861856078200 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861856078200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1502753817600).

861856078200 is an abundant number, since it is smaller than the sum of its proper divisors (2143651557000).

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

861856078200 is a wasteful number, since it uses less digits than its factorization.

861856078200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5071 (or 5062 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 51.

The spelling of 861856078200 in words is "eight hundred sixty-one billion, eight hundred fifty-six million, seventy-eight thousand, two hundred".