20688734 has 16 divisors (see below), whose sum is σ = 33941376. Its totient is φ = 9379800.

The previous prime is 20688727. The next prime is 20688751. The reversal of 20688734 is 43788602.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9749 + ... + 11679.

It is an arithmetic number, because the mean of its divisors is an integer number (2121336).

Almost surely, 2^20688734 is an apocalyptic number.

20688734 is a deficient number, since it is larger than the sum of its proper divisors (13252642).

20688734 is a wasteful number, since it uses less digits than its factorization.

20688734 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2431.

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 20688734 is about 4548.4870011906. The cubic root of 20688734 is about 274.5225168794.

The spelling of 20688734 in words is "twenty million, six hundred eighty-eight thousand, seven hundred thirty-four".