871009521 has 4 divisors (see below), whose sum is σ = 1161346032. Its totient is φ = 580673012.

The previous prime is 871009493. The next prime is 871009543. The reversal of 871009521 is 125900178.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 871009521 - 2¹⁰ = 871008497 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (871009021) 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 in 3 ways as a sum of consecutive naturals, for example, 145168251 + ... + 145168256.

It is an arithmetic number, because the mean of its divisors is an integer number (290336508).

Almost surely, 2^871009521 is an apocalyptic number.

It is an amenable number.

871009521 is a deficient number, since it is larger than the sum of its proper divisors (290336511).

871009521 is a wasteful number, since it uses less digits than its factorization.

871009521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290336510.

The product of its (nonzero) digits is 5040, while the sum is 33.

The square root of 871009521 is about 29512.8704296956. The cubic root of 871009521 is about 955.0093731891.

Adding to 871009521 its reverse (125900178), we get a palindrome (996909699).

The spelling of 871009521 in words is "eight hundred seventy-one million, nine thousand, five hundred twenty-one".