25665641 has 2 divisors, whose sum is σ = 25665642. Its totient is φ = 25665640.

The previous prime is 25665617. The next prime is 25665659. The reversal of 25665641 is 14656652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14409616 + 11256025 = 3796^2 + 3355^2 .

It is a cyclic number.

It is not a de Polignac number, because 25665641 - 2²² = 21471337 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25665671) 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, 12832820 + 12832821.

It is an arithmetic number, because the mean of its divisors is an integer number (12832821).

Almost surely, 2^25665641 is an apocalyptic number.

It is an amenable number.

25665641 is a deficient number, since it is larger than the sum of its proper divisors (1).

25665641 is an equidigital number, since it uses as much as digits as its factorization.

25665641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43200, while the sum is 35.

The square root of 25665641 is about 5066.1268243107. The cubic root of 25665641 is about 294.9742043900.

The spelling of 25665641 in words is "twenty-five million, six hundred sixty-five thousand, six hundred forty-one".