8400756409 has 2 divisors, whose sum is σ = 8400756410. Its totient is φ = 8400756408.

The previous prime is 8400756407. The next prime is 8400756421. The reversal of 8400756409 is 9046570048.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4872040000 + 3528716409 = 69800^2 + 59403^2 .

It is a cyclic number.

It is not a de Polignac number, because 8400756409 - 2¹ = 8400756407 is a prime.

Together with 8400756407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (8400756407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4200378204 + 4200378205.

It is an arithmetic number, because the mean of its divisors is an integer number (4200378205).

Almost surely, 2^8400756409 is an apocalyptic number.

It is an amenable number.

8400756409 is a deficient number, since it is larger than the sum of its proper divisors (1).

8400756409 is an equidigital number, since it uses as much as digits as its factorization.

8400756409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 241920, while the sum is 43.

The square root of 8400756409 is about 91655.6403556268. The cubic root of 8400756409 is about 2032.8537285723.

The spelling of 8400756409 in words is "eight billion, four hundred million, seven hundred fifty-six thousand, four hundred nine".