28921678307 has 4 divisors (see below), whose sum is σ = 29026088976. Its totient is φ = 28817267640.

The previous prime is 28921678301. The next prime is 28921678339. The reversal of 28921678307 is 70387612982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70387612982 = 2 ⋅35193806491.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28921678307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28921678301) 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, 52204919 + ... + 52205472.

It is an arithmetic number, because the mean of its divisors is an integer number (7256522244).

Almost surely, 2^28921678307 is an apocalyptic number.

28921678307 is a deficient number, since it is larger than the sum of its proper divisors (104410669).

28921678307 is a wasteful number, since it uses less digits than its factorization.

28921678307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104410668.

The product of its (nonzero) digits is 2032128, while the sum is 53.

The spelling of 28921678307 in words is "twenty-eight billion, nine hundred twenty-one million, six hundred seventy-eight thousand, three hundred seven".