28905223 has 2 divisors, whose sum is σ = 28905224. Its totient is φ = 28905222.

The previous prime is 28905211. The next prime is 28905229. The reversal of 28905223 is 32250982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28905223 - 2²¹ = 26808071 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28905229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14452611 + 14452612.

It is an arithmetic number, because the mean of its divisors is an integer number (14452612).

Almost surely, 2^28905223 is an apocalyptic number.

28905223 is a deficient number, since it is larger than the sum of its proper divisors (1).

28905223 is an equidigital number, since it uses as much as digits as its factorization.

28905223 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 28905223 is about 5376.3577819933. The cubic root of 28905223 is about 306.8966219212.

The spelling of 28905223 in words is "twenty-eight million, nine hundred five thousand, two hundred twenty-three".