1281438144 has 336 divisors, whose sum is σ = 4437888000. Its totient is φ = 359064576.

The previous prime is 1281438133. The next prime is 1281438173. The reversal of 1281438144 is 4418341821.

It is a happy number.

1281438144 is a `hidden beast` number, since 1 + 2 + 81 + 438 + 144 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 1281438099 and 1281438108.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8600182 + ... + 8600330.

It is an arithmetic number, because the mean of its divisors is an integer number (13208000).

Almost surely, 2^1281438144 is an apocalyptic number.

1281438144 is a gapful number since it is divisible by the number (14) 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 1281438144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2218944000).

1281438144 is an abundant number, since it is smaller than the sum of its proper divisors (3156449856).

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

1281438144 is an equidigital number, since it uses as much as digits as its factorization.

1281438144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262 (or 240 counting only the distinct ones).

The product of its digits is 24576, while the sum is 36.

The square root of 1281438144 is about 35797.1806711087. The cubic root of 1281438144 is about 1086.1735322954.

Adding to 1281438144 its reverse (4418341821), we get a palindrome (5699779965).

The spelling of 1281438144 in words is "one billion, two hundred eighty-one million, four hundred thirty-eight thousand, one hundred forty-four".