871628809 has 2 divisors, whose sum is σ = 871628810. Its totient is φ = 871628808.

The previous prime is 871628789. The next prime is 871628827. The reversal of 871628809 is 908826178.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 779526400 + 92102409 = 27920^2 + 9597^2 .

It is a cyclic number.

It is not a de Polignac number, because 871628809 - 2¹⁵ = 871596041 is a prime.

It is not a weakly prime, because it can be changed into another prime (871628839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 435814404 + 435814405.

It is an arithmetic number, because the mean of its divisors is an integer number (435814405).

Almost surely, 2^871628809 is an apocalyptic number.

It is an amenable number.

871628809 is a deficient number, since it is larger than the sum of its proper divisors (1).

871628809 is an equidigital number, since it uses as much as digits as its factorization.

871628809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 387072, while the sum is 49.

The square root of 871628809 is about 29523.3603947789. The cubic root of 871628809 is about 955.2356568740.

The spelling of 871628809 in words is "eight hundred seventy-one million, six hundred twenty-eight thousand, eight hundred nine".