25655705609 has 2 divisors, whose sum is σ = 25655705610. Its totient is φ = 25655705608.

The previous prime is 25655705563. The next prime is 25655705629. The reversal of 25655705609 is 90650755652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24748009225 + 907696384 = 157315^2 + 30128^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25655705609 is a prime.

It is not a weakly prime, because it can be changed into another prime (25655705629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12827852804 + 12827852805.

It is an arithmetic number, because the mean of its divisors is an integer number (12827852805).

Almost surely, 2^25655705609 is an apocalyptic number.

It is an amenable number.

25655705609 is a deficient number, since it is larger than the sum of its proper divisors (1).

25655705609 is an equidigital number, since it uses as much as digits as its factorization.

25655705609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2835000, while the sum is 50.

The spelling of 25655705609 in words is "twenty-five billion, six hundred fifty-five million, seven hundred five thousand, six hundred nine".