1389784328 has 8 divisors (see below), whose sum is σ = 2605845630. Its totient is φ = 694892160.

The previous prime is 1389784327. The next prime is 1389784349. The reversal of 1389784328 is 8234879831.

It can be written as a sum of positive squares in only one way, i.e., 1333564324 + 56220004 = 36518^2 + 7498^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 1389784328.

It is not an unprimeable number, because it can be changed into a prime (1389784327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86861513 + ... + 86861528.

Almost surely, 2^1389784328 is an apocalyptic number.

It is an amenable number.

1389784328 is a deficient number, since it is larger than the sum of its proper divisors (1216061302).

1389784328 is a wasteful number, since it uses less digits than its factorization.

1389784328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173723047 (or 173723043 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 53.

The square root of 1389784328 is about 37279.8112656167. The cubic root of 1389784328 is about 1115.9613065382.

The spelling of 1389784328 in words is "one billion, three hundred eighty-nine million, seven hundred eighty-four thousand, three hundred twenty-eight".