2491399049 has 2 divisors, whose sum is σ = 2491399050. Its totient is φ = 2491399048.

The previous prime is 2491399013. The next prime is 2491399067. The reversal of 2491399049 is 9409931942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1264158025 + 1227241024 = 35555^2 + 35032^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2491399049 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2491398988 and 2491399006.

It is not a weakly prime, because it can be changed into another prime (2491399849) 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 as a sum of consecutive naturals, namely, 1245699524 + 1245699525.

It is an arithmetic number, because the mean of its divisors is an integer number (1245699525).

Almost surely, 2^2491399049 is an apocalyptic number.

It is an amenable number.

2491399049 is a deficient number, since it is larger than the sum of its proper divisors (1).

2491399049 is an equidigital number, since it uses as much as digits as its factorization.

2491399049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 629856, while the sum is 50.

The square root of 2491399049 is about 49913.9163861142. The cubic root of 2491399049 is about 1355.6505817707.

The spelling of 2491399049 in words is "two billion, four hundred ninety-one million, three hundred ninety-nine thousand, forty-nine".