861333841778400 has 2304 divisors, whose sum is σ = 3615064571059200. Its totient is φ = 196525522944000.

The previous prime is 861333841778351. The next prime is 861333841778471. The reversal of 861333841778400 is 4877148333168.

861333841778400 is a `hidden beast` number, since 8 + 6 + 1 + 3 + 3 + 384 + 177 + 84 + 0 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 17448952119 + ... + 17449001481.

It is an arithmetic number, because the mean of its divisors is an integer number (1569038442300).

Almost surely, 2^{861333841778400} is an apocalyptic number.

861333841778400 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 861333841778400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1807532285529600).

861333841778400 is an abundant number, since it is smaller than the sum of its proper divisors (2753730729280800).

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

861333841778400 is a wasteful number, since it uses less digits than its factorization.

861333841778400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49530 (or 49511 counting only the distinct ones).

The product of its (nonzero) digits is 65028096, while the sum is 63.

The spelling of 861333841778400 in words is "eight hundred sixty-one trillion, three hundred thirty-three billion, eight hundred forty-one million, seven hundred seventy-eight thousand, four hundred".