20168687 has 16 divisors (see below), whose sum is σ = 25684992. Its totient is φ = 15378720.

The previous prime is 20168683. The next prime is 20168689. The reversal of 20168687 is 78686102.

It is not a de Polignac number, because 20168687 - 2² = 20168683 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20168687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20168683) 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 15 ways as a sum of consecutive naturals, for example, 833 + ... + 6405.

It is an arithmetic number, because the mean of its divisors is an integer number (1605312).

Almost surely, 2^20168687 is an apocalyptic number.

20168687 is a deficient number, since it is larger than the sum of its proper divisors (5516305).

20168687 is a wasteful number, since it uses less digits than its factorization.

20168687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5638.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 20168687 is about 4490.9561342770. The cubic root of 20168687 is about 272.2027710538.

The spelling of 20168687 in words is "twenty million, one hundred sixty-eight thousand, six hundred eighty-seven".