20728260 has 72 divisors (see below), whose sum is σ = 71862336. Its totient is φ = 4737600.

The previous prime is 20728249. The next prime is 20728271. The reversal of 20728260 is 6282702.

It is an interprime number because it is at equal distance from previous prime (20728249) and next prime (20728271).

It is a zygodrome in base 3.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6966 + ... + 9485.

It is an arithmetic number, because the mean of its divisors is an integer number (998088).

Almost surely, 2^20728260 is an apocalyptic number.

20728260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20728260 is an abundant number, since it is smaller than the sum of its proper divisors (51134076).

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

20728260 is a wasteful number, since it uses less digits than its factorization.

20728260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16473 (or 16468 counting only the distinct ones).

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

The square root of 20728260 is about 4552.8298892008. The cubic root of 20728260 is about 274.6972315197.

The spelling of 20728260 in words is "twenty million, seven hundred twenty-eight thousand, two hundred sixty".