28693009 has 2 divisors, whose sum is σ = 28693010. Its totient is φ = 28693008.

The previous prime is 28693001. The next prime is 28693039. The reversal of 28693009 is 90039682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25553025 + 3139984 = 5055^2 + 1772^2 .

It is a cyclic number.

It is not a de Polignac number, because 28693009 - 2³ = 28693001 is a prime.

It is not a weakly prime, because it can be changed into another prime (28693001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14346504 + 14346505.

It is an arithmetic number, because the mean of its divisors is an integer number (14346505).

Almost surely, 2^28693009 is an apocalyptic number.

It is an amenable number.

28693009 is a deficient number, since it is larger than the sum of its proper divisors (1).

28693009 is an equidigital number, since it uses as much as digits as its factorization.

28693009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 28693009 is about 5356.5855729186. The cubic root of 28693009 is about 306.1437268911.

The spelling of 28693009 in words is "twenty-eight million, six hundred ninety-three thousand, nine".