868198660421 has 4 divisors (see below), whose sum is σ = 868214647212. Its totient is φ = 868182673632.

The previous prime is 868198660409. The next prime is 868198660451. The reversal of 868198660421 is 124066891868.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 587960769796 + 280237890625 = 766786^2 + 529375^2 .

It is a cyclic number.

It is not a de Polignac number, because 868198660421 - 2¹⁴ = 868198644037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (868198660451) 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, 7911656 + ... + 8020641.

It is an arithmetic number, because the mean of its divisors is an integer number (217053661803).

Almost surely, 2^868198660421 is an apocalyptic number.

It is an amenable number.

868198660421 is a deficient number, since it is larger than the sum of its proper divisors (15986791).

868198660421 is a wasteful number, since it uses less digits than its factorization.

868198660421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15986790.

The product of its (nonzero) digits is 7962624, while the sum is 59.

The spelling of 868198660421 in words is "eight hundred sixty-eight billion, one hundred ninety-eight million, six hundred sixty thousand, four hundred twenty-one".