28125989 has 2 divisors, whose sum is σ = 28125990. Its totient is φ = 28125988.

The previous prime is 28125967. The next prime is 28126003. The reversal of 28125989 is 98952182.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15288100 + 12837889 = 3910^2 + 3583^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28125989 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28125289) 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, 14062994 + 14062995.

It is an arithmetic number, because the mean of its divisors is an integer number (14062995).

Almost surely, 2^28125989 is an apocalyptic number.

It is an amenable number.

28125989 is a deficient number, since it is larger than the sum of its proper divisors (1).

28125989 is an equidigital number, since it uses as much as digits as its factorization.

28125989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 103680, while the sum is 44.

The square root of 28125989 is about 5303.3941018936. The cubic root of 28125989 is about 304.1136643578.

The spelling of 28125989 in words is "twenty-eight million, one hundred twenty-five thousand, nine hundred eighty-nine".