168858261661 has 4 divisors (see below), whose sum is σ = 172044266652. Its totient is φ = 165672256672.

The previous prime is 168858261659. The next prime is 168858261701. The reversal of 168858261661 is 166162858861.

It is a happy number.

168858261661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 97465093636 + 71393168025 = 312194^2 + 267195^2 .

It is a cyclic number.

It is not a de Polignac number, because 168858261661 - 2¹ = 168858261659 is a prime.

It is a super-2 number, since 2×168858261661² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 168858261596 and 168858261605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168858261641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1593002416 + ... + 1593002521.

It is an arithmetic number, because the mean of its divisors is an integer number (43011066663).

Almost surely, 2^168858261661 is an apocalyptic number.

It is an amenable number.

168858261661 is a deficient number, since it is larger than the sum of its proper divisors (3186004991).

168858261661 is an equidigital number, since it uses as much as digits as its factorization.

168858261661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3186004990.

The product of its digits is 6635520, while the sum is 58.

The spelling of 168858261661 in words is "one hundred sixty-eight billion, eight hundred fifty-eight million, two hundred sixty-one thousand, six hundred sixty-one".