20728700 has 18 divisors (see below), whose sum is σ = 44981496. Its totient is φ = 8291440.

The previous prime is 20728699. The next prime is 20728717. The reversal of 20728700 is 782702.

It is a self number, because there is not a number n which added to its sum of digits gives 20728700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 103544 + ... + 103743.

It is an arithmetic number, because the mean of its divisors is an integer number (2498972).

Almost surely, 2^20728700 is an apocalyptic number.

20728700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20728700 is an abundant number, since it is smaller than the sum of its proper divisors (24252796).

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

20728700 is a wasteful number, since it uses less digits than its factorization.

20728700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207301 (or 207294 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 26.

The square root of 20728700 is about 4552.8782105389. The cubic root of 20728700 is about 274.6991751774.

The spelling of 20728700 in words is "twenty million, seven hundred twenty-eight thousand, seven hundred".