172103568221 has 6 divisors (see below), whose sum is σ = 186360668730. Its totient is φ = 158864832048.

The previous prime is 172103568179. The next prime is 172103568277. The reversal of 172103568221 is 122865301271.

It can be written as a sum of positive squares in 3 ways, for example, as 35402500 + 172068165721 = 5950^2 + 414811^2 .

It is not a de Polignac number, because 172103568221 - 2³⁰ = 171029826397 is a prime.

It is a super-2 number, since 2×172103568221² (a number of 23 digits) 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 (172103568281) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 509181986 + ... + 509182323.

It is an arithmetic number, because the mean of its divisors is an integer number (31060111455).

Almost surely, 2^172103568221 is an apocalyptic number.

It is an amenable number.

172103568221 is a deficient number, since it is larger than the sum of its proper divisors (14257100509).

172103568221 is a wasteful number, since it uses less digits than its factorization.

172103568221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018364335 (or 1018364322 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 38.

Adding to 172103568221 its reverse (122865301271), we get a palindrome (294968869492).

The spelling of 172103568221 in words is "one hundred seventy-two billion, one hundred three million, five hundred sixty-eight thousand, two hundred twenty-one".