1081944865 has 4 divisors (see below), whose sum is σ = 1298333844. Its totient is φ = 865555888.

The previous prime is 1081944839. The next prime is 1081944883. The reversal of 1081944865 is 5684491801.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 766846864 + 315098001 = 27692^2 + 17751^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1081944865 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108194482 + ... + 108194491.

It is an arithmetic number, because the mean of its divisors is an integer number (324583461).

Almost surely, 2^1081944865 is an apocalyptic number.

It is an amenable number.

1081944865 is a deficient number, since it is larger than the sum of its proper divisors (216388979).

1081944865 is an equidigital number, since it uses as much as digits as its factorization.

1081944865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216388978.

The product of its (nonzero) digits is 276480, while the sum is 46.

The square root of 1081944865 is about 32892.9303194471. The cubic root of 1081944865 is about 1026.6010639455.

The spelling of 1081944865 in words is "one billion, eighty-one million, nine hundred forty-four thousand, eight hundred sixty-five".