28644547009 has 27 divisors (see below), whose sum is σ = 31806278217. Its totient is φ = 25785118944.

The previous prime is 28644546977. The next prime is 28644547067. The reversal of 28644547009 is 90074544682.

The square root of 28644547009 is 169247.

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

It can be written as a sum of positive squares in 4 ways, for example, as 13248700609 + 15395846400 = 115103^2 + 124080^2 .

It is not a de Polignac number, because 28644547009 - 2⁵ = 28644546977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28644547909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 103409779 + ... + 103410055.

Almost surely, 2^28644547009 is an apocalyptic number.

28644547009 is the 169247-th square number.

28644547009 is the 84624-th centered octagonal number.

It is an amenable number.

28644547009 is a deficient number, since it is larger than the sum of its proper divisors (3161731208).

28644547009 is an frugal number, since it uses more digits than its factorization.

28644547009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674 (or 337 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 49.

Multiplying 28644547009 by its sum of digits (49), we get a square (1403582803441 = 1184729²).

The spelling of 28644547009 in words is "twenty-eight billion, six hundred forty-four million, five hundred forty-seven thousand, nine".