20818115 has 12 divisors (see below), whose sum is σ = 26539536. Its totient is φ = 15673728.

The previous prime is 20818099. The next prime is 20818121. The reversal of 20818115 is 51181802.

It is not a de Polignac number, because 20818115 - 2⁴ = 20818099 is a prime.

It is a Duffinian 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 11 ways as a sum of consecutive naturals, for example, 5759 + ... + 8648.

It is an arithmetic number, because the mean of its divisors is an integer number (2211628).

Almost surely, 2^20818115 is an apocalyptic number.

20818115 is a deficient number, since it is larger than the sum of its proper divisors (5721421).

20818115 is a wasteful number, since it uses less digits than its factorization.

20818115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14446 (or 14429 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 20818115 is about 4562.6872564312. The cubic root of 20818115 is about 275.0935879812.

Adding to 20818115 its reverse (51181802), we get a palindrome (71999917).

The spelling of 20818115 in words is "twenty million, eight hundred eighteen thousand, one hundred fifteen".