20728572 has 12 divisors (see below), whose sum is σ = 48366696. Its totient is φ = 6909520.

The previous prime is 20728571. The next prime is 20728577. The reversal of 20728572 is 27582702.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20728571) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 863679 + ... + 863702.

It is an arithmetic number, because the mean of its divisors is an integer number (4030558).

Almost surely, 2^20728572 is an apocalyptic number.

It is an amenable number.

20728572 is an abundant number, since it is smaller than the sum of its proper divisors (27638124).

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

20728572 is a wasteful number, since it uses less digits than its factorization.

20728572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1727388 (or 1727386 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 33.

The square root of 20728572 is about 4552.8641534753. The cubic root of 20728572 is about 274.6986097526.

The spelling of 20728572 in words is "twenty million, seven hundred twenty-eight thousand, five hundred seventy-two".