20728538500 has 48 divisors (see below), whose sum is σ = 46125359280. Its totient is φ = 8134963200.

The previous prime is 20728538473. The next prime is 20728538531. The reversal of 20728538500 is 583582702.

It can be written as a sum of positive squares in 8 ways, for example, as 10795625604 + 9932912896 = 103902^2 + 99664^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 364605 + ... + 417604.

It is an arithmetic number, because the mean of its divisors is an integer number (960944985).

Almost surely, 2^20728538500 is an apocalyptic number.

20728538500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20728538500 is an abundant number, since it is smaller than the sum of its proper divisors (25396820780).

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

20728538500 is a wasteful number, since it uses less digits than its factorization.

20728538500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782281 (or 782269 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 40.

The spelling of 20728538500 in words is "twenty billion, seven hundred twenty-eight million, five hundred thirty-eight thousand, five hundred".