20684718 has 12 divisors (see below), whose sum is σ = 44816928. Its totient is φ = 6894900.

The previous prime is 20684717. The next prime is 20684761. The reversal of 20684718 is 81748602.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20684717) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 574558 + ... + 574593.

It is an arithmetic number, because the mean of its divisors is an integer number (3734744).

Almost surely, 2^20684718 is an apocalyptic number.

20684718 is an abundant number, since it is smaller than the sum of its proper divisors (24132210).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20684718 is a wasteful number, since it uses less digits than its factorization.

20684718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1149159 (or 1149156 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 20684718 is about 4548.0455142841. The cubic root of 20684718 is about 274.5047527221.

It can be divided in two parts, 2068 and 4718, that added together give a triangular number (6786 = T₁₁₆).

The spelling of 20684718 in words is "twenty million, six hundred eighty-four thousand, seven hundred eighteen".