20816705 has 16 divisors (see below), whose sum is σ = 30745344. Its totient is φ = 13176000.

The previous prime is 20816701. The next prime is 20816759. The reversal of 20816705 is 50761802.

It is not a de Polignac number, because 20816705 - 2² = 20816701 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20816701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22421 + ... + 23330.

It is an arithmetic number, because the mean of its divisors is an integer number (1921584).

Almost surely, 2^20816705 is an apocalyptic number.

It is an amenable number.

20816705 is a deficient number, since it is larger than the sum of its proper divisors (9928639).

20816705 is a wasteful number, since it uses less digits than its factorization.

20816705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45776.

The product of its (nonzero) digits is 3360, while the sum is 29.

The square root of 20816705 is about 4562.5327396086. The cubic root of 20816705 is about 275.0873771929.

The spelling of 20816705 in words is "twenty million, eight hundred sixteen thousand, seven hundred five".