20510000117 has 4 divisors (see below), whose sum is σ = 21171613056. Its totient is φ = 19848387180.

The previous prime is 20510000087. The next prime is 20510000123. The reversal of 20510000117 is 71100001502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 71100001502 = 2 ⋅35550000751.

It is a cyclic number.

It is not a de Polignac number, because 20510000117 - 2¹⁴ = 20509983733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20510000095 and 20510000104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20510000417) 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, 330806423 + ... + 330806484.

It is an arithmetic number, because the mean of its divisors is an integer number (5292903264).

Almost surely, 2^20510000117 is an apocalyptic number.

It is an amenable number.

20510000117 is a deficient number, since it is larger than the sum of its proper divisors (661612939).

20510000117 is an equidigital number, since it uses as much as digits as its factorization.

20510000117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661612938.

The product of its (nonzero) digits is 70, while the sum is 17.

Adding to 20510000117 its reverse (71100001502), we get a palindrome (91610001619).

The spelling of 20510000117 in words is "twenty billion, five hundred ten million, one hundred seventeen", and thus it is an aban number.