2638549409 has 2 divisors, whose sum is σ = 2638549410. Its totient is φ = 2638549408.

The previous prime is 2638549391. The next prime is 2638549457. The reversal of 2638549409 is 9049458362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1985593600 + 652955809 = 44560^2 + 25553^2 .

It is a cyclic number.

It is not a de Polignac number, because 2638549409 - 2⁸ = 2638549153 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2638549909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1319274704 + 1319274705.

It is an arithmetic number, because the mean of its divisors is an integer number (1319274705).

Almost surely, 2^2638549409 is an apocalyptic number.

It is an amenable number.

2638549409 is a deficient number, since it is larger than the sum of its proper divisors (1).

2638549409 is an equidigital number, since it uses as much as digits as its factorization.

2638549409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1866240, while the sum is 50.

The square root of 2638549409 is about 51366.8123305311. The cubic root of 2638549409 is about 1381.8314633181.

The spelling of 2638549409 in words is "two billion, six hundred thirty-eight million, five hundred forty-nine thousand, four hundred nine".