20416805 has 4 divisors (see below), whose sum is σ = 24500172. Its totient is φ = 16333440.

The previous prime is 20416793. The next prime is 20416807. The reversal of 20416805 is 50861402.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4464769 + 15952036 = 2113^2 + 3994^2 .

It is not a de Polignac number, because 20416805 - 2⁴ = 20416789 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 (20416807) 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, 2041676 + ... + 2041685.

It is an arithmetic number, because the mean of its divisors is an integer number (6125043).

Almost surely, 2^20416805 is an apocalyptic number.

It is an amenable number.

20416805 is a deficient number, since it is larger than the sum of its proper divisors (4083367).

20416805 is an equidigital number, since it uses as much as digits as its factorization.

20416805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4083366.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20416805 is about 4518.4958780550. The cubic root of 20416805 is about 273.3144502455.

The spelling of 20416805 in words is "twenty million, four hundred sixteen thousand, eight hundred five".