28893989 has 2 divisors, whose sum is σ = 28893990. Its totient is φ = 28893988.

The previous prime is 28893973. The next prime is 28894009. The reversal of 28893989 is 98939882.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28890625 + 3364 = 5375^2 + 58^2 .

It is a cyclic number.

It is not a de Polignac number, because 28893989 - 2⁴ = 28893973 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28893089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14446994 + 14446995.

It is an arithmetic number, because the mean of its divisors is an integer number (14446995).

Almost surely, 2^28893989 is an apocalyptic number.

It is an amenable number.

28893989 is a deficient number, since it is larger than the sum of its proper divisors (1).

28893989 is an equidigital number, since it uses as much as digits as its factorization.

28893989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 56.

The square root of 28893989 is about 5375.3129211238. The cubic root of 28893989 is about 306.8568583648.

The spelling of 28893989 in words is "twenty-eight million, eight hundred ninety-three thousand, nine hundred eighty-nine".