28123545391 has 2 divisors, whose sum is σ = 28123545392. Its totient is φ = 28123545390.

The previous prime is 28123545341. The next prime is 28123545397. The reversal of 28123545391 is 19354532182.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28123545391 - 2¹³ = 28123537199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28123545397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14061772695 + 14061772696.

It is an arithmetic number, because the mean of its divisors is an integer number (14061772696).

Almost surely, 2^28123545391 is an apocalyptic number.

28123545391 is a deficient number, since it is larger than the sum of its proper divisors (1).

28123545391 is an equidigital number, since it uses as much as digits as its factorization.

28123545391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 259200, while the sum is 43.

The spelling of 28123545391 in words is "twenty-eight billion, one hundred twenty-three million, five hundred forty-five thousand, three hundred ninety-one".