20728741 has 8 divisors (see below), whose sum is σ = 22698144. Its totient is φ = 18773520.

The previous prime is 20728733. The next prime is 20728759. The reversal of 20728741 is 14782702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20728741 - 2³ = 20728733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20728781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 355 + ... + 6448.

It is an arithmetic number, because the mean of its divisors is an integer number (2837268).

Almost surely, 2^20728741 is an apocalyptic number.

It is an amenable number.

20728741 is a deficient number, since it is larger than the sum of its proper divisors (1969403).

20728741 is a wasteful number, since it uses less digits than its factorization.

20728741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7091.

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 20728741 is about 4552.8827131829. The cubic root of 20728741 is about 274.6993562896.

The spelling of 20728741 in words is "twenty million, seven hundred twenty-eight thousand, seven hundred forty-one".