28907789 has 2 divisors, whose sum is σ = 28907790. Its totient is φ = 28907788.

The previous prime is 28907777. The next prime is 28907807. The reversal of 28907789 is 98770982.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16362025 + 12545764 = 4045^2 + 3542^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28907789 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 (28907719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14453894 + 14453895.

It is an arithmetic number, because the mean of its divisors is an integer number (14453895).

Almost surely, 2^28907789 is an apocalyptic number.

It is an amenable number.

28907789 is a deficient number, since it is larger than the sum of its proper divisors (1).

28907789 is an equidigital number, since it uses as much as digits as its factorization.

28907789 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 508032, while the sum is 50.

The square root of 28907789 is about 5376.5964140895. The cubic root of 28907789 is about 306.9057030185.

The spelling of 28907789 in words is "twenty-eight million, nine hundred seven thousand, seven hundred eighty-nine".