1288435680 has 384 divisors, whose sum is σ = 5208053760. Its totient is φ = 291409920.

The previous prime is 1288435679. The next prime is 1288435691. The reversal of 1288435680 is 865348821.

1288435680 is a `hidden beast` number, since 1 + 2 + 8 + 84 + 3 + 568 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4142725 + ... + 4143035.

It is an arithmetic number, because the mean of its divisors is an integer number (13562640).

Almost surely, 2^1288435680 is an apocalyptic number.

1288435680 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 1288435680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2604026880).

1288435680 is an abundant number, since it is smaller than the sum of its proper divisors (3919618080).

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

1288435680 is a wasteful number, since it uses less digits than its factorization.

1288435680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 479 (or 465 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 1288435680 is about 35894.7862509306. The cubic root of 1288435680 is about 1088.1470299424.

The spelling of 1288435680 in words is "one billion, two hundred eighty-eight million, four hundred thirty-five thousand, six hundred eighty".