20716847 has 4 divisors (see below), whose sum is σ = 21068040. Its totient is φ = 20365656.

The previous prime is 20716789. The next prime is 20716873. The reversal of 20716847 is 74861702.

It is a happy number.

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 20716847 - 2¹² = 20712751 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 (20712847) 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, 175508 + ... + 175625.

It is an arithmetic number, because the mean of its divisors is an integer number (5267010).

Almost surely, 2^20716847 is an apocalyptic number.

20716847 is a deficient number, since it is larger than the sum of its proper divisors (351193).

20716847 is an equidigital number, since it uses as much as digits as its factorization.

20716847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351192.

The product of its (nonzero) digits is 18816, while the sum is 35.

The square root of 20716847 is about 4551.5763203532. The cubic root of 20716847 is about 274.6468060767.

The spelling of 20716847 in words is "twenty million, seven hundred sixteen thousand, eight hundred forty-seven".