28978889 has 2 divisors, whose sum is σ = 28978890. Its totient is φ = 28978888.

The previous prime is 28978867. The next prime is 28978913. The reversal of 28978889 is 98887982.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14500864 + 14478025 = 3808^2 + 3805^2 .

It is a cyclic number.

It is not a de Polignac number, because 28978889 - 2⁸ = 28978633 is a prime.

It is a Chen prime.

It is a weakly prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14489444 + 14489445.

It is an arithmetic number, because the mean of its divisors is an integer number (14489445).

Almost surely, 2^28978889 is an apocalyptic number.

It is an amenable number.

28978889 is a deficient number, since it is larger than the sum of its proper divisors (1).

28978889 is an equidigital number, since it uses as much as digits as its factorization.

28978889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4644864, while the sum is 59.

The square root of 28978889 is about 5383.2043431399. The cubic root of 28978889 is about 307.1571131141.

The spelling of 28978889 in words is "twenty-eight million, nine hundred seventy-eight thousand, eight hundred eighty-nine".