1287005440 has 144 divisors (see below), whose sum is σ = 3543805440. Its totient is φ = 438681600.

The previous prime is 1287005431. The next prime is 1287005441. The reversal of 1287005440 is 445007821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287005441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2141140 + ... + 2141740.

It is an arithmetic number, because the mean of its divisors is an integer number (24609760).

Almost surely, 2^1287005440 is an apocalyptic number.

1287005440 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 1287005440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1771902720).

1287005440 is an abundant number, since it is smaller than the sum of its proper divisors (2256800000).

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

1287005440 is an equidigital number, since it uses as much as digits as its factorization.

1287005440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868 (or 854 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 31.

The square root of 1287005440 is about 35874.8580484996. The cubic root of 1287005440 is about 1087.7442449596.

The spelling of 1287005440 in words is "one billion, two hundred eighty-seven million, five thousand, four hundred forty".