20808115 has 8 divisors (see below), whose sum is σ = 25579008. Its totient is φ = 16240320.

The previous prime is 20808107. The next prime is 20808233. The reversal of 20808115 is 51180802.

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

It is not a de Polignac number, because 20808115 - 2³ = 20808107 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20808115.

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, 50547 + ... + 50956.

It is an arithmetic number, because the mean of its divisors is an integer number (3197376).

Almost surely, 2^20808115 is an apocalyptic number.

20808115 is a deficient number, since it is larger than the sum of its proper divisors (4770893).

20808115 is a wasteful number, since it uses less digits than its factorization.

20808115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101549.

The product of its (nonzero) digits is 640, while the sum is 25.

The square root of 20808115 is about 4561.5912793673. The cubic root of 20808115 is about 275.0495337770.

Adding to 20808115 its reverse (51180802), we get a palindrome (71988917).

The spelling of 20808115 in words is "twenty million, eight hundred eight thousand, one hundred fifteen".