20708117 has 4 divisors (see below), whose sum is σ = 21422220. Its totient is φ = 19994016.

The previous prime is 20708101. The next prime is 20708137. The reversal of 20708117 is 71180702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71180702 = 2 ⋅35590351.

It can be written as a sum of positive squares in 2 ways, for example, as 3352561 + 17355556 = 1831^2 + 4166^2 .

It is a cyclic number.

It is not a de Polignac number, because 20708117 - 2⁴ = 20708101 is a prime.

It is a super-2 number, since 2×20708117² = 857652219371378, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20708137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 357008 + ... + 357065.

It is an arithmetic number, because the mean of its divisors is an integer number (5355555).

Almost surely, 2^20708117 is an apocalyptic number.

It is an amenable number.

20708117 is a deficient number, since it is larger than the sum of its proper divisors (714103).

20708117 is an equidigital number, since it uses as much as digits as its factorization.

20708117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 714102.

The product of its (nonzero) digits is 784, while the sum is 26.

The square root of 20708117 is about 4550.6172108847. The cubic root of 20708117 is about 274.6082222857.

Adding to 20708117 its reverse (71180702), we get a palindrome (91888819).

The spelling of 20708117 in words is "twenty million, seven hundred eight thousand, one hundred seventeen".