1287536640 has 360 divisors, whose sum is σ = 4605205248. Its totient is φ = 306708480.

The previous prime is 1287536623. The next prime is 1287536651. The reversal of 1287536640 is 466357821.

It is a junction number, because it is equal to n+sod(n) for n = 1287536592 and 1287536601.

It is a congruent number.

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, 41533425 + ... + 41533455.

Almost surely, 2^1287536640 is an apocalyptic number.

1287536640 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 1287536640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2302602624).

1287536640 is an abundant number, since it is smaller than the sum of its proper divisors (3317668608).

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

1287536640 is an equidigital number, since it uses as much as digits as its factorization.

1287536640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 42.

The square root of 1287536640 is about 35882.2607983388. The cubic root of 1287536640 is about 1087.8938766156.

The spelling of 1287536640 in words is "one billion, two hundred eighty-seven million, five hundred thirty-six thousand, six hundred forty".