20172017 has 8 divisors (see below), whose sum is σ = 20607816. Its totient is φ = 19740672.

The previous prime is 20172007. The next prime is 20172037. The reversal of 20172017 is 71027102.

It can be written as a sum of positive squares in 4 ways, for example, as 7612081 + 12559936 = 2759^2 + 3544^2 .

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 20172017 - 2⁴ = 20172001 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20172017.

It is not an unprimeable number, because it can be changed into a prime (20172007) 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, 8993 + ... + 11009.

It is an arithmetic number, because the mean of its divisors is an integer number (2575977).

Almost surely, 2^20172017 is an apocalyptic number.

It is an amenable number.

20172017 is a deficient number, since it is larger than the sum of its proper divisors (435799).

20172017 is a wasteful number, since it uses less digits than its factorization.

20172017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2227.

The product of its (nonzero) digits is 196, while the sum is 20.

The square root of 20172017 is about 4491.3268640793. The cubic root of 20172017 is about 272.2177511290.

Adding to 20172017 its reverse (71027102), we get a palindrome (91199119).

The spelling of 20172017 in words is "twenty million, one hundred seventy-two thousand, seventeen".