25657 has 2 divisors, whose sum is σ = 25658. Its totient is φ = 25656.

The previous prime is 25643. The next prime is 25667. The reversal of 25657 is 75652.

It is a happy number.

25657 is nontrivially palindromic in base 12.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19881 + 5776 = 141^2 + 76^2 .

It is a cyclic number.

It is not a de Polignac number, because 25657 - 2¹¹ = 23609 is a prime.

It is a d-powerful number, because it can be written as 2¹⁰ + 5² + 6⁵ + 5² + 7⁵ .

25657 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (25667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12828 + 12829.

It is an arithmetic number, because the mean of its divisors is an integer number (12829).

2²⁵⁶⁵⁷ is an apocalyptic number.

It is an amenable number.

25657 is a deficient number, since it is larger than the sum of its proper divisors (1).

25657 is an equidigital number, since it uses as much as digits as its factorization.

25657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2100, while the sum is 25.

The square root of 25657 is about 160.1780259586. The cubic root of 25657 is about 29.4941097116.

It can be divided in two parts, 2565 and 7, that multiplied together give a triangular number (17955 = T₁₈₉).

The spelling of 25657 in words is "twenty-five thousand, six hundred fifty-seven".