25671209 has 2 divisors, whose sum is σ = 25671210. Its totient is φ = 25671208.

The previous prime is 25671181. The next prime is 25671221. The reversal of 25671209 is 90217652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17405584 + 8265625 = 4172^2 + 2875^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25671209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25671809) 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, 12835604 + 12835605.

It is an arithmetic number, because the mean of its divisors is an integer number (12835605).

Almost surely, 2^25671209 is an apocalyptic number.

It is an amenable number.

25671209 is a deficient number, since it is larger than the sum of its proper divisors (1).

25671209 is an equidigital number, since it uses as much as digits as its factorization.

25671209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 25671209 is about 5066.6763267452. The cubic root of 25671209 is about 294.9955337828.

The spelling of 25671209 in words is "twenty-five million, six hundred seventy-one thousand, two hundred nine".