168218641 has 2 divisors, whose sum is σ = 168218642. Its totient is φ = 168218640.

The previous prime is 168218639. The next prime is 168218653. The reversal of 168218641 is 146812861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166539025 + 1679616 = 12905^2 + 1296^2 .

It is a cyclic number.

It is not a de Polignac number, because 168218641 - 2¹ = 168218639 is a prime.

It is a super-2 number, since 2×168218641² = 56595022359773762, which contains 22 as substring.

Together with 168218639, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 168218641.

It is not a weakly prime, because it can be changed into another prime (168213641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84109320 + 84109321.

It is an arithmetic number, because the mean of its divisors is an integer number (84109321).

Almost surely, 2^168218641 is an apocalyptic number.

It is an amenable number.

168218641 is a deficient number, since it is larger than the sum of its proper divisors (1).

168218641 is an equidigital number, since it uses as much as digits as its factorization.

168218641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18432, while the sum is 37.

The square root of 168218641 is about 12969.9129141255. The cubic root of 168218641 is about 552.0241021210.

The spelling of 168218641 in words is "one hundred sixty-eight million, two hundred eighteen thousand, six hundred forty-one".