1281552427728 has 30 divisors (see below), whose sum is σ = 3586566864114. Its totient is φ = 427184142528.

The previous prime is 1281552427709. The next prime is 1281552427747. The reversal of 1281552427728 is 8277242551821.

It is a happy number.

1281552427728 is a `hidden beast` number, since 1 + 2 + 81 + 552 + 4 + 2 + 7 + 7 + 2 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (1281552427709) and next prime (1281552427747).

It can be written as a sum of positive squares in only one way, i.e., 1262279214144 + 19273213584 = 1123512^2 + 138828^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4449834675 + ... + 4449834962.

Almost surely, 2^{1281552427728} is an apocalyptic number.

1281552427728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1281552427728 is an abundant number, since it is smaller than the sum of its proper divisors (2305014436386).

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

1281552427728 is a wasteful number, since it uses less digits than its factorization.

1281552427728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8899669651 (or 8899669642 counting only the distinct ones).

The product of its digits is 5017600, while the sum is 54.

The spelling of 1281552427728 in words is "one trillion, two hundred eighty-one billion, five hundred fifty-two million, four hundred twenty-seven thousand, seven hundred twenty-eight".