28998628991 has 4 divisors (see below), whose sum is σ = 29004318984. Its totient is φ = 28992939000.

The previous prime is 28998628969. The next prime is 28998628993. The reversal of 28998628991 is 19982689982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19982689982 = 2 ⋅9991344991.

It is a cyclic number.

It is not a de Polignac number, because 28998628991 - 2⁶ = 28998628927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28998628993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2837345 + ... + 2847546.

It is an arithmetic number, because the mean of its divisors is an integer number (7251079746).

Almost surely, 2^28998628991 is an apocalyptic number.

28998628991 is a deficient number, since it is larger than the sum of its proper divisors (5689993).

28998628991 is an equidigital number, since it uses as much as digits as its factorization.

28998628991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5689992.

The product of its digits is 80621568, while the sum is 71.

The spelling of 28998628991 in words is "twenty-eight billion, nine hundred ninety-eight million, six hundred twenty-eight thousand, nine hundred ninety-one".