3639394728 has 24 divisors (see below), whose sum is σ = 9856694250. Its totient is φ = 1213131552.

The previous prime is 3639394721. The next prime is 3639394739. The reversal of 3639394728 is 8274939363.

It can be written as a sum of positive squares in only one way, i.e., 3602160324 + 37234404 = 60018^2 + 6102^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (3639394721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 25273503 + ... + 25273646.

Almost surely, 2^3639394728 is an apocalyptic number.

It is an amenable number.

3639394728 is an abundant number, since it is smaller than the sum of its proper divisors (6217299522).

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

3639394728 is a wasteful number, since it uses less digits than its factorization.

3639394728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50547161 (or 50547154 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 54.

The square root of 3639394728 is about 60327.3961645951. The cubic root of 3639394728 is about 1538.1890682479.

The spelling of 3639394728 in words is "three billion, six hundred thirty-nine million, three hundred ninety-four thousand, seven hundred twenty-eight".