868158682821 has 24 divisors (see below), whose sum is σ = 1327838180760. Its totient is φ = 544699908096.

The previous prime is 868158682817. The next prime is 868158682843. The reversal of 868158682821 is 128286851868.

868158682821 is a `hidden beast` number, since 8 + 6 + 8 + 1 + 586 + 8 + 28 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 218288921796 + 649869761025 = 467214^2 + 806145^2 .

It is not a de Polignac number, because 868158682821 - 2² = 868158682817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (868158682021) 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 23 ways as a sum of consecutive naturals, for example, 3200965 + ... + 3461573.

It is an arithmetic number, because the mean of its divisors is an integer number (55326590865).

Almost surely, 2^868158682821 is an apocalyptic number.

It is an amenable number.

868158682821 is a deficient number, since it is larger than the sum of its proper divisors (459679497939).

868158682821 is a wasteful number, since it uses less digits than its factorization.

868158682821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282405 (or 282402 counting only the distinct ones).

The product of its digits is 23592960, while the sum is 63.

The spelling of 868158682821 in words is "eight hundred sixty-eight billion, one hundred fifty-eight million, six hundred eighty-two thousand, eight hundred twenty-one".