25541609 has 2 divisors, whose sum is σ = 25541610. Its totient is φ = 25541608.

The previous prime is 25541603. The next prime is 25541623. The reversal of 25541609 is 90614552.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21529600 + 4012009 = 4640^2 + 2003^2 .

It is a cyclic number.

It is not a de Polignac number, because 25541609 - 2¹² = 25537513 is a prime.

It is not a weakly prime, because it can be changed into another prime (25541603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12770804 + 12770805.

It is an arithmetic number, because the mean of its divisors is an integer number (12770805).

Almost surely, 2^25541609 is an apocalyptic number.

It is an amenable number.

25541609 is a deficient number, since it is larger than the sum of its proper divisors (1).

25541609 is an equidigital number, since it uses as much as digits as its factorization.

25541609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 25541609 is about 5053.8706948239. The cubic root of 25541609 is about 294.4982719307.

The spelling of 25541609 in words is "twenty-five million, five hundred forty-one thousand, six hundred nine".