20682720 has 144 divisors (see below), whose sum is σ = 72176832. Its totient is φ = 5391360.

The previous prime is 20682719. The next prime is 20682743. The reversal of 20682720 is 2728602.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 76185 + ... + 76455.

It is an arithmetic number, because the mean of its divisors is an integer number (501228).

Almost surely, 2^20682720 is an apocalyptic number.

20682720 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 20682720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36088416).

20682720 is an abundant number, since it is smaller than the sum of its proper divisors (51494112).

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

20682720 is a wasteful number, since it uses less digits than its factorization.

20682720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345 (or 334 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 20682720 is about 4547.8258541857. The cubic root of 20682720 is about 274.4959140204.

The spelling of 20682720 in words is "twenty million, six hundred eighty-two thousand, seven hundred twenty".