25728905 has 16 divisors (see below), whose sum is σ = 33002640. Its totient is φ = 19187712.

The previous prime is 25728889. The next prime is 25728917. The reversal of 25728905 is 50982752.

It can be written as a sum of positive squares in 8 ways, for example, as 3721 + 25725184 = 61^2 + 5072^2 .

It is a cyclic number.

It is not a de Polignac number, because 25728905 - 2⁴ = 25728889 is a prime.

It is a Curzon number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 7877 + ... + 10653.

It is an arithmetic number, because the mean of its divisors is an integer number (2062665).

Almost surely, 2^25728905 is an apocalyptic number.

It is an amenable number.

25728905 is a deficient number, since it is larger than the sum of its proper divisors (7273735).

25728905 is a wasteful number, since it uses less digits than its factorization.

25728905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2908.

The product of its (nonzero) digits is 50400, while the sum is 38.

The square root of 25728905 is about 5072.3668045598. The cubic root of 25728905 is about 295.2163690820.

It can be divided in two parts, 257 and 28905, that multiplied together give a triangular number (7428585 = T₃₈₅₄).

The spelling of 25728905 in words is "twenty-five million, seven hundred twenty-eight thousand, nine hundred five".