20704847 has 4 divisors (see below), whose sum is σ = 20812320. Its totient is φ = 20597376.

The previous prime is 20704843. The next prime is 20704883. The reversal of 20704847 is 74840702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20704847 - 2² = 20704843 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 (20704843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53447 + ... + 53832.

It is an arithmetic number, because the mean of its divisors is an integer number (5203080).

Almost surely, 2^20704847 is an apocalyptic number.

20704847 is a deficient number, since it is larger than the sum of its proper divisors (107473).

20704847 is a wasteful number, since it uses less digits than its factorization.

20704847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107472.

The product of its (nonzero) digits is 12544, while the sum is 32.

The square root of 20704847 is about 4550.2579047786. The cubic root of 20704847 is about 274.5937671462.

The spelling of 20704847 in words is "twenty million, seven hundred four thousand, eight hundred forty-seven".