1809481444 has 9 divisors (see below), whose sum is σ = 3166741417. Its totient is φ = 904698184.

The previous prime is 1809481433. The next prime is 1809481447. The reversal of 1809481444 is 4441849081.

The square root of 1809481444 is 42538.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1058721444 + 750760000 = 32538^2 + 27400^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1809481444.

It is not an unprimeable number, because it can be changed into a prime (1809481447) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 74442 + ... + 95710.

Almost surely, 2^1809481444 is an apocalyptic number.

1809481444 is the 42538-th square number.

It is an amenable number.

1809481444 is a deficient number, since it is larger than the sum of its proper divisors (1357259973).

1809481444 is an frugal number, since it uses more digits than its factorization.

1809481444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42542 (or 21271 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 43.

The cubic root of 1809481444 is about 1218.5725138551.

Multiplying 1809481444 by its product of nonzero digits (147456), we get a square (266818895806464 = 16334592²).

The spelling of 1809481444 in words is "one billion, eight hundred nine million, four hundred eighty-one thousand, four hundred forty-four".