20815113 has 16 divisors (see below), whose sum is σ = 30355200. Its totient is φ = 12582480.

The previous prime is 20815099. The next prime is 20815117. The reversal of 20815113 is 31151802.

It is not a de Polignac number, because 20815113 - 2⁶ = 20815049 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20815113.

It is not an unprimeable number, because it can be changed into a prime (20815117) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 19918 + ... + 20936.

It is an arithmetic number, because the mean of its divisors is an integer number (1897200).

Almost surely, 2^20815113 is an apocalyptic number.

It is an amenable number.

20815113 is a deficient number, since it is larger than the sum of its proper divisors (9540087).

20815113 is a wasteful number, since it uses less digits than its factorization.

20815113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1652.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 20815113 is about 4562.3582717713. The cubic root of 20815113 is about 275.0803643913.

Adding to 20815113 its reverse (31151802), we get a palindrome (51966915).

The spelling of 20815113 in words is "twenty million, eight hundred fifteen thousand, one hundred thirteen".