2559138661 has 4 divisors (see below), whose sum is σ = 2559553024. Its totient is φ = 2558724300.

The previous prime is 2559138653. The next prime is 2559138713. The reversal of 2559138661 is 1668319552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2559138661 - 2³ = 2559138653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2559138161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 197775 + ... + 210316.

It is an arithmetic number, because the mean of its divisors is an integer number (639888256).

Almost surely, 2^2559138661 is an apocalyptic number.

It is an amenable number.

2559138661 is a deficient number, since it is larger than the sum of its proper divisors (414363).

2559138661 is an equidigital number, since it uses as much as digits as its factorization.

2559138661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414362.

The product of its digits is 388800, while the sum is 46.

The square root of 2559138661 is about 50587.9299932306. The cubic root of 2559138661 is about 1367.8273162799.

The spelling of 2559138661 in words is "two billion, five hundred fifty-nine million, one hundred thirty-eight thousand, six hundred sixty-one".