20686875 has 80 divisors (see below), whose sum is σ = 40487040. Its totient is φ = 9280000.

The previous prime is 20686873. The next prime is 20686879. The reversal of 20686875 is 57868602.

It is not a de Polignac number, because 20686875 - 2¹ = 20686873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20686871) 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 79 ways as a sum of consecutive naturals, for example, 350596 + ... + 350654.

It is an arithmetic number, because the mean of its divisors is an integer number (506088).

Almost surely, 2^20686875 is an apocalyptic number.

20686875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20686875 is a deficient number, since it is larger than the sum of its proper divisors (19800165).

20686875 is a wasteful number, since it uses less digits than its factorization.

20686875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110 (or 95 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 42.

The square root of 20686875 is about 4548.2826429324. The cubic root of 20686875 is about 274.5142941651.

The spelling of 20686875 in words is "twenty million, six hundred eighty-six thousand, eight hundred seventy-five".