20915115 has 32 divisors (see below), whose sum is σ = 36261120. Its totient is φ = 10233216.

The previous prime is 20915113. The next prime is 20915123. The reversal of 20915115 is 51151902.

It is not a de Polignac number, because 20915115 - 2¹ = 20915113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20915113) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 54996 + ... + 55374.

It is an arithmetic number, because the mean of its divisors is an integer number (1133160).

Almost surely, 2^20915115 is an apocalyptic number.

20915115 is a deficient number, since it is larger than the sum of its proper divisors (15346005).

20915115 is a wasteful number, since it uses less digits than its factorization.

20915115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 683.

The product of its (nonzero) digits is 450, while the sum is 24.

The square root of 20915115 is about 4573.3046038942. The cubic root of 20915115 is about 275.5201834570.

The spelling of 20915115 in words is "twenty million, nine hundred fifteen thousand, one hundred fifteen".