20809065 has 8 divisors (see below), whose sum is σ = 33294528. Its totient is φ = 11098160.

The previous prime is 20809057. The next prime is 20809073. The reversal of 20809065 is 56090802.

It is an interprime number because it is at equal distance from previous prime (20809057) and next prime (20809073).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20809065 - 2³ = 20809057 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 693621 + ... + 693650.

It is an arithmetic number, because the mean of its divisors is an integer number (4161816).

Almost surely, 2^20809065 is an apocalyptic number.

It is an amenable number.

20809065 is a deficient number, since it is larger than the sum of its proper divisors (12485463).

20809065 is a wasteful number, since it uses less digits than its factorization.

20809065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1387279.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 20809065 is about 4561.6954085077. The cubic root of 20809065 is about 275.0537195331.

Adding to 20809065 its reverse (56090802), we get a palindrome (76899867).

The spelling of 20809065 in words is "twenty million, eight hundred nine thousand, sixty-five".