28724897 has 2 divisors, whose sum is σ = 28724898. Its totient is φ = 28724896.

The previous prime is 28724867. The next prime is 28724909. The reversal of 28724897 is 79842782.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15358561 + 13366336 = 3919^2 + 3656^2 .

It is a cyclic number.

It is not a de Polignac number, because 28724897 - 2¹⁰ = 28723873 is a prime.

It is not a weakly prime, because it can be changed into another prime (28724837) 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, 14362448 + 14362449.

It is an arithmetic number, because the mean of its divisors is an integer number (14362449).

Almost surely, 2^28724897 is an apocalyptic number.

It is an amenable number.

28724897 is a deficient number, since it is larger than the sum of its proper divisors (1).

28724897 is an equidigital number, since it uses as much as digits as its factorization.

28724897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 451584, while the sum is 47.

The square root of 28724897 is about 5359.5612693578. The cubic root of 28724897 is about 306.2570959344.

The spelling of 28724897 in words is "twenty-eight million, seven hundred twenty-four thousand, eight hundred ninety-seven".