28689889 has 2 divisors, whose sum is σ = 28689890. Its totient is φ = 28689888.

The previous prime is 28689851. The next prime is 28689953. The reversal of 28689889 is 98898682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28037025 + 652864 = 5295^2 + 808^2 .

It is a cyclic number.

It is not a de Polignac number, because 28689889 - 2²¹ = 26592737 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28689839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14344944 + 14344945.

It is an arithmetic number, because the mean of its divisors is an integer number (14344945).

Almost surely, 2^28689889 is an apocalyptic number.

It is an amenable number.

28689889 is a deficient number, since it is larger than the sum of its proper divisors (1).

28689889 is an equidigital number, since it uses as much as digits as its factorization.

28689889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3981312, while the sum is 58.

The square root of 28689889 is about 5356.2943347057. The cubic root of 28689889 is about 306.1326300759.

The spelling of 28689889 in words is "twenty-eight million, six hundred eighty-nine thousand, eight hundred eighty-nine".