25694561 has 2 divisors, whose sum is σ = 25694562. Its totient is φ = 25694560.

The previous prime is 25694549. The next prime is 25694569. The reversal of 25694561 is 16549652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15171025 + 10523536 = 3895^2 + 3244^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25694561 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (25694569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12847280 + 12847281.

It is an arithmetic number, because the mean of its divisors is an integer number (12847281).

Almost surely, 2^25694561 is an apocalyptic number.

It is an amenable number.

25694561 is a deficient number, since it is larger than the sum of its proper divisors (1).

25694561 is an equidigital number, since it uses as much as digits as its factorization.

25694561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64800, while the sum is 38.

The square root of 25694561 is about 5068.9802722047. The cubic root of 25694561 is about 295.0849549441.

The spelling of 25694561 in words is "twenty-five million, six hundred ninety-four thousand, five hundred sixty-one".