172021107218 has 32 divisors (see below), whose sum is σ = 265851210240. Its totient is φ = 83419277760.

The previous prime is 172021107217. The next prime is 172021107229. The reversal of 172021107218 is 812701120271.

It is a super-2 number, since 2×172021107218² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (172021107217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44994455 + ... + 44998277.

It is an arithmetic number, because the mean of its divisors is an integer number (8307850320).

Almost surely, 2^172021107218 is an apocalyptic number.

172021107218 is a deficient number, since it is larger than the sum of its proper divisors (93830103022).

172021107218 is a wasteful number, since it uses less digits than its factorization.

172021107218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5642.

The product of its (nonzero) digits is 3136, while the sum is 32.

Adding to 172021107218 its reverse (812701120271), we get a palindrome (984722227489).

The spelling of 172021107218 in words is "one hundred seventy-two billion, twenty-one million, one hundred seven thousand, two hundred eighteen".