20172220117 has 4 divisors (see below), whose sum is σ = 23053965856. Its totient is φ = 17290474380.

The previous prime is 20172220097. The next prime is 20172220139. The reversal of 20172220117 is 71102227102.

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.

It is a cyclic number.

It is not a de Polignac number, because 20172220117 - 2²³ = 20163831509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20172220091 and 20172220100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20172220147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1440872859 + ... + 1440872872.

It is an arithmetic number, because the mean of its divisors is an integer number (5763491464).

Almost surely, 2^20172220117 is an apocalyptic number.

It is an amenable number.

20172220117 is a deficient number, since it is larger than the sum of its proper divisors (2881745739).

20172220117 is an equidigital number, since it uses as much as digits as its factorization.

20172220117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2881745738.

The product of its (nonzero) digits is 784, while the sum is 25.

Adding to 20172220117 its reverse (71102227102), we get a palindrome (91274447219).

The spelling of 20172220117 in words is "twenty billion, one hundred seventy-two million, two hundred twenty thousand, one hundred seventeen".