1281944564 has 24 divisors (see below), whose sum is σ = 2267640648. Its totient is φ = 634083840.

The previous prime is 1281944561. The next prime is 1281944603. The reversal of 1281944564 is 4654491821.

It can be written as a sum of positive squares in 4 ways, for example, as 18852964 + 1263091600 = 4342^2 + 35540^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281944561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 141944 + ... + 150704.

It is an arithmetic number, because the mean of its divisors is an integer number (94485027).

Almost surely, 2^1281944564 is an apocalyptic number.

It is an amenable number.

1281944564 is a deficient number, since it is larger than the sum of its proper divisors (985696084).

1281944564 is a wasteful number, since it uses less digits than its factorization.

1281944564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9155 (or 9153 counting only the distinct ones).

The product of its digits is 276480, while the sum is 44.

The square root of 1281944564 is about 35804.2534344734. The cubic root of 1281944564 is about 1086.3165974804.

The spelling of 1281944564 in words is "one billion, two hundred eighty-one million, nine hundred forty-four thousand, five hundred sixty-four".