25478857 has 2 divisors, whose sum is σ = 25478858. Its totient is φ = 25478856.

The previous prime is 25478821. The next prime is 25478861. The reversal of 25478857 is 75887452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24000201 + 1478656 = 4899^2 + 1216^2 .

It is a cyclic number.

It is not a de Polignac number, because 25478857 - 2⁷ = 25478729 is a prime.

It is not a weakly prime, because it can be changed into another prime (25478897) 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, 12739428 + 12739429.

It is an arithmetic number, because the mean of its divisors is an integer number (12739429).

Almost surely, 2^25478857 is an apocalyptic number.

It is an amenable number.

25478857 is a deficient number, since it is larger than the sum of its proper divisors (1).

25478857 is an equidigital number, since it uses as much as digits as its factorization.

25478857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 627200, while the sum is 46.

The square root of 25478857 is about 5047.6585661077. The cubic root of 25478857 is about 294.2568944101.

It can be divided in two parts, 25478 and 857, that added together give a triangular number (26335 = T₂₂₉).

The spelling of 25478857 in words is "twenty-five million, four hundred seventy-eight thousand, eight hundred fifty-seven".