28720344706 has 16 divisors (see below), whose sum is σ = 44757343800. Its totient is φ = 13805481088.

The previous prime is 28720344701. The next prime is 28720344707. The reversal of 28720344706 is 60744302782.

28720344706 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 22369689225 + 6350655481 = 149565^2 + 79691^2 .

It is not an unprimeable number, because it can be changed into a prime (28720344701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1049101 + ... + 1076128.

Almost surely, 2^28720344706 is an apocalyptic number.

28720344706 is a deficient number, since it is larger than the sum of its proper divisors (16036999094).

28720344706 is a wasteful number, since it uses less digits than its factorization.

28720344706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2125493.

The product of its (nonzero) digits is 451584, while the sum is 43.

The spelling of 28720344706 in words is "twenty-eight billion, seven hundred twenty million, three hundred forty-four thousand, seven hundred six".