28320625281 has 16 divisors (see below), whose sum is σ = 41060329856. Its totient is φ = 17258870016.

The previous prime is 28320625279. The next prime is 28320625301. The reversal of 28320625281 is 18252602382.

It is not a de Polignac number, because 28320625281 - 2¹ = 28320625279 is a prime.

It is a super-2 number, since 2×28320625281² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28320625231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3521080 + ... + 3529113.

It is an arithmetic number, because the mean of its divisors is an integer number (2566270616).

Almost surely, 2^28320625281 is an apocalyptic number.

It is an amenable number.

28320625281 is a deficient number, since it is larger than the sum of its proper divisors (12739704575).

28320625281 is a wasteful number, since it uses less digits than its factorization.

28320625281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7050312.

The product of its (nonzero) digits is 92160, while the sum is 39.

The spelling of 28320625281 in words is "twenty-eight billion, three hundred twenty million, six hundred twenty-five thousand, two hundred eighty-one".