28720000049 has 4 divisors (see below), whose sum is σ = 30929230836. Its totient is φ = 26510769264.

The previous prime is 28720000027. The next prime is 28720000063. The reversal of 28720000049 is 94000002782.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17386268449 + 11333731600 = 131857^2 + 106460^2 .

It is a cyclic number.

It is not a de Polignac number, because 28720000049 - 2²⁸ = 28451564593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28720000009) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1104615374 + ... + 1104615399.

It is an arithmetic number, because the mean of its divisors is an integer number (7732307709).

Almost surely, 2^28720000049 is an apocalyptic number.

It is an amenable number.

28720000049 is a deficient number, since it is larger than the sum of its proper divisors (2209230787).

28720000049 is a wasteful number, since it uses less digits than its factorization.

28720000049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2209230786.

The product of its (nonzero) digits is 8064, while the sum is 32.

The spelling of 28720000049 in words is "twenty-eight billion, seven hundred twenty million, forty-nine", and thus it is an aban number.