1261787340800 has 168 divisors, whose sum is σ = 3576051619536. Its totient is φ = 432612311040.

The previous prime is 1261787340797. The next prime is 1261787340839. The reversal of 1261787340800 is 80437871621.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 993524 + ... + 1873676.

Almost surely, 2^{1261787340800} is an apocalyptic number.

1261787340800 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 1261787340800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1788025809768).

1261787340800 is an abundant number, since it is smaller than the sum of its proper divisors (2314264278736).

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

1261787340800 is an frugal number, since it uses more digits than its factorization.

1261787340800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 880196 (or 880167 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 47.

The spelling of 1261787340800 in words is "one trillion, two hundred sixty-one billion, seven hundred eighty-seven million, three hundred forty thousand, eight hundred".