2606398649 has 4 divisors (see below), whose sum is σ = 2655576036. Its totient is φ = 2557221264.

The previous prime is 2606398637. The next prime is 2606398657. The reversal of 2606398649 is 9468936062.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9468936062 = 2 ⋅4734468031.

It can be written as a sum of positive squares in 2 ways, for example, as 1359249424 + 1247149225 = 36868^2 + 35315^2 .

It is a cyclic number.

It is not a de Polignac number, because 2606398649 - 2⁸ = 2606398393 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53), and also a Moran number because the ratio is a prime number: 49177333 = 2606398649 / (2 + 6 + 0 + 6 + 3 + 9 + 8 + 6 + 4 + 9).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2606398649.

It is not an unprimeable number, because it can be changed into a prime (2606398679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24588614 + ... + 24588719.

It is an arithmetic number, because the mean of its divisors is an integer number (663894009).

Almost surely, 2^2606398649 is an apocalyptic number.

It is an amenable number.

2606398649 is a deficient number, since it is larger than the sum of its proper divisors (49177387).

2606398649 is an equidigital number, since it uses as much as digits as its factorization.

2606398649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49177386.

The product of its (nonzero) digits is 3359232, while the sum is 53.

The square root of 2606398649 is about 51052.9004954665. The cubic root of 2606398649 is about 1376.1959664405.

The spelling of 2606398649 in words is "two billion, six hundred six million, three hundred ninety-eight thousand, six hundred forty-nine".