168728681 has 8 divisors (see below), whose sum is σ = 185891328. Its totient is φ = 151870000.

The previous prime is 168728671. The next prime is 168728701. The reversal of 168728681 is 186827861.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 168728681 - 2¹⁸ = 168466537 is a prime.

It is a super-2 number, since 2×168728681² = 56938735583999522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (168728671) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74825 + ... + 77046.

It is an arithmetic number, because the mean of its divisors is an integer number (23236416).

Almost surely, 2^168728681 is an apocalyptic number.

168728681 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

168728681 is a deficient number, since it is larger than the sum of its proper divisors (17162647).

168728681 is a wasteful number, since it uses less digits than its factorization.

168728681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151983.

The product of its digits is 258048, while the sum is 47.

The square root of 168728681 is about 12989.5604621558. The cubic root of 168728681 is about 552.5814527441.

The spelling of 168728681 in words is "one hundred sixty-eight million, seven hundred twenty-eight thousand, six hundred eighty-one".