1281136544 has 48 divisors (see below), whose sum is σ = 2599433928. Its totient is φ = 621084672.

The previous prime is 1281136543. The next prime is 1281136583. The reversal of 1281136544 is 4456311821.

It can be written as a sum of positive squares in 4 ways, for example, as 557526544 + 723610000 = 23612^2 + 26900^2 .

It is not an unprimeable number, because it can be changed into a prime (1281136543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 368864 + ... + 372320.

Almost surely, 2^1281136544 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1281136544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1299716964).

1281136544 is an abundant number, since it is smaller than the sum of its proper divisors (1318297384).

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

1281136544 is a wasteful number, since it uses less digits than its factorization.

1281136544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3817 (or 3809 counting only the distinct ones).

The product of its digits is 23040, while the sum is 35.

The square root of 1281136544 is about 35792.9678009522. The cubic root of 1281136544 is about 1086.0883114720.

The spelling of 1281136544 in words is "one billion, two hundred eighty-one million, one hundred thirty-six thousand, five hundred forty-four".