28332989 has 2 divisors, whose sum is σ = 28332990. Its totient is φ = 28332988.

The previous prime is 28332973. The next prime is 28332991. The reversal of 28332989 is 98923382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28270489 + 62500 = 5317^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 28332989 - 2⁴ = 28332973 is a prime.

It is a super-3 number, since 3×28332989³ (a number of 23 digits) contains 333 as substring.

Together with 28332991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28332929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14166494 + 14166495.

It is an arithmetic number, because the mean of its divisors is an integer number (14166495).

Almost surely, 2^28332989 is an apocalyptic number.

It is an amenable number.

28332989 is a deficient number, since it is larger than the sum of its proper divisors (1).

28332989 is an equidigital number, since it uses as much as digits as its factorization.

28332989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 44.

The square root of 28332989 is about 5322.8741296409. The cubic root of 28332989 is about 304.8579074756.

The spelling of 28332989 in words is "twenty-eight million, three hundred thirty-two thousand, nine hundred eighty-nine".