168693681 has 16 divisors (see below), whose sum is σ = 242464320. Its totient is φ = 103709760.

The previous prime is 168693673. The next prime is 168693697. The reversal of 168693681 is 186396861.

It is not a de Polignac number, because 168693681 - 2³ = 168693673 is a prime.

It is a super-2 number, since 2×168693681² = 56915116018659522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 168693681.

It is not an unprimeable number, because it can be changed into a prime (168693671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65386 + ... + 67916.

It is an arithmetic number, because the mean of its divisors is an integer number (15154020).

Almost surely, 2^168693681 is an apocalyptic number.

It is an amenable number.

168693681 is a deficient number, since it is larger than the sum of its proper divisors (73770639).

168693681 is a wasteful number, since it uses less digits than its factorization.

168693681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4256.

The product of its digits is 373248, while the sum is 48.

The square root of 168693681 is about 12988.2131565508. The cubic root of 168693681 is about 552.5432421128.

The spelling of 168693681 in words is "one hundred sixty-eight million, six hundred ninety-three thousand, six hundred eighty-one".