28781809306 has 16 divisors (see below), whose sum is σ = 44365037544. Its totient is φ = 13993910784.

The previous prime is 28781809289. The next prime is 28781809361. The reversal of 28781809306 is 60390818782.

It can be written as a sum of positive squares in 4 ways, for example, as 13757178681 + 15024630625 = 117291^2 + 122575^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18786 + ... + 240658.

Almost surely, 2^28781809306 is an apocalyptic number.

28781809306 is a deficient number, since it is larger than the sum of its proper divisors (15583228238).

28781809306 is a wasteful number, since it uses less digits than its factorization.

28781809306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223665.

The product of its (nonzero) digits is 1161216, while the sum is 52.

The spelling of 28781809306 in words is "twenty-eight billion, seven hundred eighty-one million, eight hundred nine thousand, three hundred six".