1285778188800 has 900 divisors, whose sum is σ = 5535918638910. Its totient is φ = 293880545280.

The previous prime is 1285778188771. The next prime is 1285778188801. The reversal of 1285778188800 is 88818775821.

It can be written as a sum of positive squares in 3 ways, for example, as 1009976760576 + 275801428224 = 1004976^2 + 525168^2 .

It is a tau number, because it is divible by the number of its divisors (900).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (1285778188801) by changing a digit.

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 89 ways as a sum of consecutive naturals, for example, 50790546 + ... + 50815854.

Almost surely, 2^{1285778188800} is an apocalyptic number.

1285778188800 is a gapful number since it is divisible by the number (10) 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 1285778188800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2767959319455).

1285778188800 is an abundant number, since it is smaller than the sum of its proper divisors (4250140450110).

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

1285778188800 is an equidigital number, since it uses as much as digits as its factorization.

1285778188800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25363 (or 25326 counting only the distinct ones).

The product of its (nonzero) digits is 16056320, while the sum is 63.

The spelling of 1285778188800 in words is "one trillion, two hundred eighty-five billion, seven hundred seventy-eight million, one hundred eighty-eight thousand, eight hundred".