25645654609 has 2 divisors, whose sum is σ = 25645654610. Its totient is φ = 25645654608.

The previous prime is 25645654607. The next prime is 25645654733. The reversal of 25645654609 is 90645654652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14310858384 + 11334796225 = 119628^2 + 106465^2 .

It is a cyclic number.

It is not a de Polignac number, because 25645654609 - 2¹ = 25645654607 is a prime.

Together with 25645654607, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (25645654607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12822827304 + 12822827305.

It is an arithmetic number, because the mean of its divisors is an integer number (12822827305).

Almost surely, 2^25645654609 is an apocalyptic number.

It is an amenable number.

25645654609 is a deficient number, since it is larger than the sum of its proper divisors (1).

25645654609 is an equidigital number, since it uses as much as digits as its factorization.

25645654609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776000, while the sum is 52.

The spelling of 25645654609 in words is "twenty-five billion, six hundred forty-five million, six hundred fifty-four thousand, six hundred nine".