28688478451 has 4 divisors (see below), whose sum is σ = 28967007472. Its totient is φ = 28409949432.

The previous prime is 28688478449. The next prime is 28688478457. The reversal of 28688478451 is 15487488682.

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

It is a cyclic number.

It is not a de Polignac number, because 28688478451 - 2¹ = 28688478449 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28688478451.

It is not an unprimeable number, because it can be changed into a prime (28688478457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 139264356 + ... + 139264561.

It is an arithmetic number, because the mean of its divisors is an integer number (7241751868).

Almost surely, 2^28688478451 is an apocalyptic number.

28688478451 is a deficient number, since it is larger than the sum of its proper divisors (278529021).

28688478451 is a wasteful number, since it uses less digits than its factorization.

28688478451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278529020.

The product of its digits is 27525120, while the sum is 61.

The spelling of 28688478451 in words is "twenty-eight billion, six hundred eighty-eight million, four hundred seventy-eight thousand, four hundred fifty-one".