20688134 has 4 divisors (see below), whose sum is σ = 31032204. Its totient is φ = 10344066.

The previous prime is 20688121. The next prime is 20688197. The reversal of 20688134 is 43188602.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 20688134.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5172032 + ... + 5172035.

It is an arithmetic number, because the mean of its divisors is an integer number (7758051).

Almost surely, 2^20688134 is an apocalyptic number.

20688134 is a deficient number, since it is larger than the sum of its proper divisors (10344070).

20688134 is a wasteful number, since it uses less digits than its factorization.

20688134 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10344069.

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 20688134 is about 4548.4210447143. The cubic root of 20688134 is about 274.5198630179.

The spelling of 20688134 in words is "twenty million, six hundred eighty-eight thousand, one hundred thirty-four".