20117517 has 8 divisors (see below), whose sum is σ = 30655296. Its totient is φ = 11495712.

The previous prime is 20117497. The next prime is 20117519. The reversal of 20117517 is 71571102.

It is a happy number.

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

It is not a de Polignac number, because 20117517 - 2⁸ = 20117261 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20117519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 478968 + ... + 479009.

It is an arithmetic number, because the mean of its divisors is an integer number (3831912).

Almost surely, 2^20117517 is an apocalyptic number.

It is an amenable number.

20117517 is a deficient number, since it is larger than the sum of its proper divisors (10537779).

20117517 is an equidigital number, since it uses as much as digits as its factorization.

20117517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 957987.

The product of its (nonzero) digits is 490, while the sum is 24.

The square root of 20117517 is about 4485.2555111164. The cubic root of 20117517 is about 271.9723741046.

Adding to 20117517 its reverse (71571102), we get a palindrome (91688619).

The spelling of 20117517 in words is "twenty million, one hundred seventeen thousand, five hundred seventeen".