861782678400 has 576 divisors, whose sum is σ = 3307192968960. Its totient is φ = 196664832000.

The previous prime is 861782678399. The next prime is 861782678401. The reversal of 861782678400 is 4876287168.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (861782678399) and next prime (861782678401).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861782678401) 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 71 ways as a sum of consecutive naturals, for example, 428533395 + ... + 428535405.

It is an arithmetic number, because the mean of its divisors is an integer number (5741654460).

Almost surely, 2^861782678400 is an apocalyptic number.

861782678400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861782678400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1653596484480).

861782678400 is an abundant number, since it is smaller than the sum of its proper divisors (2445410290560).

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

861782678400 is a wasteful number, since it uses less digits than its factorization.

861782678400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2963 (or 2939 counting only the distinct ones).

The product of its (nonzero) digits is 7225344, while the sum is 57.

The spelling of 861782678400 in words is "eight hundred sixty-one billion, seven hundred eighty-two million, six hundred seventy-eight thousand, four hundred".