8172909449 has 2 divisors, whose sum is σ = 8172909450. Its totient is φ = 8172909448.

The previous prime is 8172909421. The next prime is 8172909491. The reversal of 8172909449 is 9449092718.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6126975625 + 2045933824 = 78275^2 + 45232^2 .

It is a cyclic number.

It is not a de Polignac number, because 8172909449 - 2³² = 3877942153 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 8172909449.

It is not a weakly prime, because it can be changed into another prime (8172909649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4086454724 + 4086454725.

It is an arithmetic number, because the mean of its divisors is an integer number (4086454725).

Almost surely, 2^8172909449 is an apocalyptic number.

It is an amenable number.

8172909449 is a deficient number, since it is larger than the sum of its proper divisors (1).

8172909449 is an equidigital number, since it uses as much as digits as its factorization.

8172909449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1306368, while the sum is 53.

The square root of 8172909449 is about 90404.1450874903. The cubic root of 8172909449 is about 2014.3065382138.

The spelling of 8172909449 in words is "eight billion, one hundred seventy-two million, nine hundred nine thousand, four hundred forty-nine".