2591779658849 has 4 divisors (see below), whose sum is σ = 2593310540436. Its totient is φ = 2590248777264.

The previous prime is 2591779658843. The next prime is 2591779658917. The reversal of 2591779658849 is 9488569771952.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 619912149025 + 1971867509824 = 787345^2 + 1404232^2 .

It is a cyclic number.

It is not a de Polignac number, because 2591779658849 - 2¹² = 2591779654753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2591779658843) 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, 765438254 + ... + 765441639.

It is an arithmetic number, because the mean of its divisors is an integer number (648327635109).

Almost surely, 2^{2591779658849} is an apocalyptic number.

It is an amenable number.

2591779658849 is a deficient number, since it is larger than the sum of its proper divisors (1530881587).

2591779658849 is a wasteful number, since it uses less digits than its factorization.

2591779658849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1530881586.

The product of its digits is 2743372800, while the sum is 80.

The spelling of 2591779658849 in words is "two trillion, five hundred ninety-one billion, seven hundred seventy-nine million, six hundred fifty-eight thousand, eight hundred forty-nine".