28390728907 has 2 divisors, whose sum is σ = 28390728908. Its totient is φ = 28390728906.

The previous prime is 28390728893. The next prime is 28390728997. The reversal of 28390728907 is 70982709382.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28390728907 is a prime.

It is not a weakly prime, because it can be changed into another prime (28390728997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14195364453 + 14195364454.

It is an arithmetic number, because the mean of its divisors is an integer number (14195364454).

Almost surely, 2^28390728907 is an apocalyptic number.

28390728907 is a deficient number, since it is larger than the sum of its proper divisors (1).

28390728907 is an equidigital number, since it uses as much as digits as its factorization.

28390728907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3048192, while the sum is 55.

The spelling of 28390728907 in words is "twenty-eight billion, three hundred ninety million, seven hundred twenty-eight thousand, nine hundred seven".