20415317 has 8 divisors (see below), whose sum is σ = 23279256. Its totient is φ = 17736192.

The previous prime is 20415313. The next prime is 20415319. The reversal of 20415317 is 71351402.

It can be written as a sum of positive squares in 4 ways, for example, as 4844401 + 15570916 = 2201^2 + 3946^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20415317 - 2² = 20415313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20415292 and 20415301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20415313) 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, 45968 + ... + 46409.

It is an arithmetic number, because the mean of its divisors is an integer number (2909907).

Almost surely, 2^20415317 is an apocalyptic number.

It is an amenable number.

20415317 is a deficient number, since it is larger than the sum of its proper divisors (2863939).

20415317 is a wasteful number, since it uses less digits than its factorization.

20415317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92407.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 20415317 is about 4518.3312184921. The cubic root of 20415317 is about 273.3078102614.

Adding to 20415317 its reverse (71351402), we get a palindrome (91766719).

The spelling of 20415317 in words is "twenty million, four hundred fifteen thousand, three hundred seventeen".