868855521 has 12 divisors (see below), whose sum is σ = 1211034608. Its totient is φ = 554051784.

The previous prime is 868855517. The next prime is 868855529. The reversal of 868855521 is 125558868.

It is not a de Polignac number, because 868855521 - 2² = 868855517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (868855529) 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 11 ways as a sum of consecutive naturals, for example, 272155 + ... + 275328.

Almost surely, 2^868855521 is an apocalyptic number.

It is an amenable number.

868855521 is a deficient number, since it is larger than the sum of its proper divisors (342179087).

868855521 is a wasteful number, since it uses less digits than its factorization.

868855521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 547532 (or 547509 counting only the distinct ones).

The product of its digits is 768000, while the sum is 48.

The square root of 868855521 is about 29476.3552869075. The cubic root of 868855521 is about 954.2214796791.

The spelling of 868855521 in words is "eight hundred sixty-eight million, eight hundred fifty-five thousand, five hundred twenty-one".