20704320 has 336 divisors, whose sum is σ = 88757760. Its totient is φ = 4313088.

The previous prime is 20704309. The next prime is 20704379. The reversal of 20704320 is 2340702.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20704293 and 20704302.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 262041 + ... + 262119.

It is an arithmetic number, because the mean of its divisors is an integer number (264160).

Almost surely, 2^20704320 is an apocalyptic number.

20704320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20704320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44378880).

20704320 is an abundant number, since it is smaller than the sum of its proper divisors (68053440).

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

20704320 is a wasteful number, since it uses less digits than its factorization.

20704320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 109 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 18.

The square root of 20704320 is about 4550.1999956046. The cubic root of 20704320 is about 274.5914373835.

The spelling of 20704320 in words is "twenty million, seven hundred four thousand, three hundred twenty".