20415205 has 8 divisors (see below), whose sum is σ = 25288704. Its totient is φ = 15805200.

The previous prime is 20415203. The next prime is 20415221. The reversal of 20415205 is 50251402.

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

It is not a de Polignac number, because 20415205 - 2¹ = 20415203 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20415203) 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 7 ways as a sum of consecutive naturals, for example, 65701 + ... + 66010.

It is an arithmetic number, because the mean of its divisors is an integer number (3161088).

Almost surely, 2^20415205 is an apocalyptic number.

It is an amenable number.

20415205 is a deficient number, since it is larger than the sum of its proper divisors (4873499).

20415205 is a wasteful number, since it uses less digits than its factorization.

20415205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131747.

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 20415205 is about 4518.3188245187. The cubic root of 20415205 is about 273.3073104646.

Adding to 20415205 its reverse (50251402), we get a palindrome (70666607).

The spelling of 20415205 in words is "twenty million, four hundred fifteen thousand, two hundred five".