869191049 has 2 divisors, whose sum is σ = 869191050. Its totient is φ = 869191048.

The previous prime is 869191033. The next prime is 869191097. The reversal of 869191049 is 940191968.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 550747024 + 318444025 = 23468^2 + 17845^2 .

It is a cyclic number.

It is not a de Polignac number, because 869191049 - 2⁴ = 869191033 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 869190994 and 869191012.

It is not a weakly prime, because it can be changed into another prime (869191019) 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, 434595524 + 434595525.

It is an arithmetic number, because the mean of its divisors is an integer number (434595525).

Almost surely, 2^869191049 is an apocalyptic number.

It is an amenable number.

869191049 is a deficient number, since it is larger than the sum of its proper divisors (1).

869191049 is an equidigital number, since it uses as much as digits as its factorization.

869191049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 869191049 is about 29482.0462146032. The cubic root of 869191049 is about 954.3442951961.

The spelling of 869191049 in words is "eight hundred sixty-nine million, one hundred ninety-one thousand, forty-nine".