It is a happy number.
It is a tau number, because it is divible by the number of its divisors (40).
It is a congruent number.
It is an unprimeable number.
Almost surely, 220660720 is an apocalyptic number.
20660720 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 20660720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24607800).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
20660720 is a wasteful number, since it uses less digits than its factorization.
20660720 is an evil number, because the sum of its binary digits is even.
The square root of 20660720 is about 4545.4064724731. The cubic root of 20660720 is about 274.3985533162.
The spelling of 20660720 in words is "twenty million, six hundred sixty thousand, seven hundred twenty".