25728457 has 2 divisors, whose sum is σ = 25728458. Its totient is φ = 25728456.

The previous prime is 25728449. The next prime is 25728487. The reversal of 25728457 is 75482752.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18567481 + 7160976 = 4309^2 + 2676^2 .

It is a cyclic number.

It is not a de Polignac number, because 25728457 - 2³ = 25728449 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25728487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12864228 + 12864229.

It is an arithmetic number, because the mean of its divisors is an integer number (12864229).

Almost surely, 2^25728457 is an apocalyptic number.

It is an amenable number.

25728457 is a deficient number, since it is larger than the sum of its proper divisors (1).

25728457 is an equidigital number, since it uses as much as digits as its factorization.

25728457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 156800, while the sum is 40.

The square root of 25728457 is about 5072.3226435234. The cubic root of 25728457 is about 295.2146556045.

The spelling of 25728457 in words is "twenty-five million, seven hundred twenty-eight thousand, four hundred fifty-seven".