20728767 has 8 divisors (see below), whose sum is σ = 27659520. Its totient is φ = 13808600.

The previous prime is 20728759. The next prime is 20728781. The reversal of 20728767 is 76782702.

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 20728767 - 2³ = 20728759 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20728717) 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, 5584 + ... + 8522.

It is an arithmetic number, because the mean of its divisors is an integer number (3457440).

Almost surely, 2^20728767 is an apocalyptic number.

20728767 is a deficient number, since it is larger than the sum of its proper divisors (6930753).

20728767 is a wasteful number, since it uses less digits than its factorization.

20728767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5293.

The product of its (nonzero) digits is 65856, while the sum is 39.

The square root of 20728767 is about 4552.8855685159. The cubic root of 20728767 is about 274.6994711411.

The spelling of 20728767 in words is "twenty million, seven hundred twenty-eight thousand, seven hundred sixty-seven".