20728425520 has 40 divisors (see below), whose sum is σ = 52574826960. Its totient is φ = 7537608960.

The previous prime is 20728425517. The next prime is 20728425527. The reversal of 20728425520 is 2552482702.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 20728425520.

It is not an unprimeable number, because it can be changed into a prime (20728425527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11776635 + ... + 11778394.

It is an arithmetic number, because the mean of its divisors is an integer number (1314370674).

Almost surely, 2^20728425520 is an apocalyptic number.

20728425520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20728425520 is an abundant number, since it is smaller than the sum of its proper divisors (31846401440).

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

20728425520 is a wasteful number, since it uses less digits than its factorization.

20728425520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23555053 (or 23555047 counting only the distinct ones).

The product of its (nonzero) digits is 89600, while the sum is 37.

The spelling of 20728425520 in words is "twenty billion, seven hundred twenty-eight million, four hundred twenty-five thousand, five hundred twenty".