1280521200800 has 144 divisors (see below), whose sum is σ = 3135348621720. Its totient is φ = 510691184640.

The previous prime is 1280521200797. The next prime is 1280521200839. The reversal of 1280521200800 is 80021250821.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 7117284496 + 1273403916304 = 84364^2 + 1128452^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 536006006 + ... + 536008394.

Almost surely, 2^{1280521200800} is an apocalyptic number.

1280521200800 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 1280521200800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1567674310860).

1280521200800 is an abundant number, since it is smaller than the sum of its proper divisors (1854827420920).

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

1280521200800 is a wasteful number, since it uses less digits than its factorization.

1280521200800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4115 (or 4102 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 29.

The spelling of 1280521200800 in words is "one trillion, two hundred eighty billion, five hundred twenty-one million, two hundred thousand, eight hundred".