168805864421 has 2 divisors, whose sum is σ = 168805864422. Its totient is φ = 168805864420.

The previous prime is 168805864417. The next prime is 168805864459. The reversal of 168805864421 is 124468508861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 134717627521 + 34088236900 = 367039^2 + 184630^2 .

It is a cyclic number.

It is not a de Polignac number, because 168805864421 - 2² = 168805864417 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (168805804421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84402932210 + 84402932211.

It is an arithmetic number, because the mean of its divisors is an integer number (84402932211).

Almost surely, 2^168805864421 is an apocalyptic number.

It is an amenable number.

168805864421 is a deficient number, since it is larger than the sum of its proper divisors (1).

168805864421 is an equidigital number, since it uses as much as digits as its factorization.

168805864421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2949120, while the sum is 53.

The spelling of 168805864421 in words is "one hundred sixty-eight billion, eight hundred five million, eight hundred sixty-four thousand, four hundred twenty-one".