168821797 has 2 divisors, whose sum is σ = 168821798. Its totient is φ = 168821796.

The previous prime is 168821773. The next prime is 168821857. The reversal of 168821797 is 797128861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 95531076 + 73290721 = 9774^2 + 8561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-168821797 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 168821797.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (168821717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84410898 + 84410899.

It is an arithmetic number, because the mean of its divisors is an integer number (84410899).

Almost surely, 2^168821797 is an apocalyptic number.

It is an amenable number.

168821797 is a deficient number, since it is larger than the sum of its proper divisors (1).

168821797 is an equidigital number, since it uses as much as digits as its factorization.

168821797 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 49.

The square root of 168821797 is about 12993.1442307087. The cubic root of 168821797 is about 552.6830847683.

The spelling of 168821797 in words is "one hundred sixty-eight million, eight hundred twenty-one thousand, seven hundred ninety-seven".