7167181221 has 6 divisors (see below), whose sum is σ = 10352595110. Its totient is φ = 4778120808.

The previous prime is 7167181213. The next prime is 7167181297. The reversal of 7167181221 is 1221817617.

It can be written as a sum of positive squares in only one way, i.e., 6344122500 + 823058721 = 79650^2 + 28689^2 .

It is not a de Polignac number, because 7167181221 - 2³ = 7167181213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7167181211) 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, 398176726 + ... + 398176743.

Almost surely, 2^7167181221 is an apocalyptic number.

It is an amenable number.

7167181221 is a deficient number, since it is larger than the sum of its proper divisors (3185413889).

7167181221 is a wasteful number, since it uses less digits than its factorization.

7167181221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 796353475 (or 796353472 counting only the distinct ones).

The product of its digits is 9408, while the sum is 36.

The square root of 7167181221 is about 84659.2063570171. The cubic root of 7167181221 is about 1928.0403943381.

Adding to 7167181221 its reverse (1221817617), we get a palindrome (8388998838).

The spelling of 7167181221 in words is "seven billion, one hundred sixty-seven million, one hundred eighty-one thousand, two hundred twenty-one".