851378781000 has 384 divisors, whose sum is σ = 3001250828160. Its totient is φ = 199271296000.

The previous prime is 851378780977. The next prime is 851378781031. The reversal of 851378781000 is 187873158.

It is a happy number.

It is a super-2 number, since 2×851378781000² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 27737662 + ... + 27768338.

It is an arithmetic number, because the mean of its divisors is an integer number (7815757365).

Almost surely, 2^851378781000 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 851378781000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1500625414080).

851378781000 is an abundant number, since it is smaller than the sum of its proper divisors (2149872047160).

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

851378781000 is a wasteful number, since it uses less digits than its factorization.

851378781000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30770 (or 30727 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 48.

The spelling of 851378781000 in words is "eight hundred fifty-one billion, three hundred seventy-eight million, seven hundred eighty-one thousand".