7217223138 has 12 divisors (see below), whose sum is σ = 15637316838. Its totient is φ = 2405741040.

The previous prime is 7217223137. The next prime is 7217223149. The reversal of 7217223138 is 8313227127.

It can be written as a sum of positive squares in only one way, i.e., 4873017249 + 2344205889 = 69807^2 + 48417^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7217223137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 200478403 + ... + 200478438.

Almost surely, 2^7217223138 is an apocalyptic number.

7217223138 is an abundant number, since it is smaller than the sum of its proper divisors (8420093700).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7217223138 is a wasteful number, since it uses less digits than its factorization.

7217223138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400956849 (or 400956846 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 7217223138 is about 84954.2414361991. The cubic root of 7217223138 is about 1932.5172428475.

The spelling of 7217223138 in words is "seven billion, two hundred seventeen million, two hundred twenty-three thousand, one hundred thirty-eight".