2565559609 has 2 divisors, whose sum is σ = 2565559610. Its totient is φ = 2565559608.

The previous prime is 2565559589. The next prime is 2565559621. The reversal of 2565559609 is 9069555652.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2525364009 + 40195600 = 50253^2 + 6340^2 .

It is a cyclic number.

It is not a de Polignac number, because 2565559609 - 2²¹ = 2563462457 is a prime.

It is a super-2 number, since 2×2565559609² = 13164192214664465762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2565559649) 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, 1282779804 + 1282779805.

It is an arithmetic number, because the mean of its divisors is an integer number (1282779805).

Almost surely, 2^2565559609 is an apocalyptic number.

It is an amenable number.

2565559609 is a deficient number, since it is larger than the sum of its proper divisors (1).

2565559609 is an equidigital number, since it uses as much as digits as its factorization.

2565559609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3645000, while the sum is 52.

The square root of 2565559609 is about 50651.3534764867. The cubic root of 2565559609 is about 1368.9703327489.

It can be divided in two parts, 25655 and 59609, that added together give a square (85264 = 292²).

The spelling of 2565559609 in words is "two billion, five hundred sixty-five million, five hundred fifty-nine thousand, six hundred nine".