28879981979 has 4 divisors (see below), whose sum is σ = 28895619984. Its totient is φ = 28864343976.

The previous prime is 28879981909. The next prime is 28879981987. The reversal of 28879981979 is 97918997882.

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 28879981979 - 2²⁴ = 28863204763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28879981909) 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, 7816232 + ... + 7819925.

It is an arithmetic number, because the mean of its divisors is an integer number (7223904996).

Almost surely, 2^28879981979 is an apocalyptic number.

28879981979 is a deficient number, since it is larger than the sum of its proper divisors (15638005).

28879981979 is a wasteful number, since it uses less digits than its factorization.

28879981979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15638004.

The product of its digits is 329204736, while the sum is 77.

The spelling of 28879981979 in words is "twenty-eight billion, eight hundred seventy-nine million, nine hundred eighty-one thousand, nine hundred seventy-nine".