1288013540 has 72 divisors (see below), whose sum is σ = 3075763320. Its totient is φ = 452193280.

The previous prime is 1288013539. The next prime is 1288013563. The reversal of 1288013540 is 453108821.

It can be written as a sum of positive squares in 4 ways, for example, as 495616 + 1287517924 = 704^2 + 35882^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1288013497 and 1288013506.

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, 61004 + ... + 79356.

It is an arithmetic number, because the mean of its divisors is an integer number (42718935).

Almost surely, 2^1288013540 is an apocalyptic number.

1288013540 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 1288013540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1537881660).

1288013540 is an abundant number, since it is smaller than the sum of its proper divisors (1787749780).

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

1288013540 is a wasteful number, since it uses less digits than its factorization.

1288013540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18413 (or 18400 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 32.

The square root of 1288013540 is about 35888.9055280319. The cubic root of 1288013540 is about 1088.0281776602.

The spelling of 1288013540 in words is "one billion, two hundred eighty-eight million, thirteen thousand, five hundred forty".