7168921 has 2 divisors, whose sum is σ = 7168922. Its totient is φ = 7168920.

The previous prime is 7168919. The next prime is 7168927. The reversal of 7168921 is 1298617.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4410000 + 2758921 = 2100^2 + 1661^2 .

It is an emirp because it is prime and its reverse (1298617) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7168921 - 2¹ = 7168919 is a prime.

Together with 7168919, it forms a pair of twin primes.

7168921 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (7168927) 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 as a sum of consecutive naturals, namely, 3584460 + 3584461.

It is an arithmetic number, because the mean of its divisors is an integer number (3584461).

Almost surely, 2^7168921 is an apocalyptic number.

It is an amenable number.

7168921 is a deficient number, since it is larger than the sum of its proper divisors (1).

7168921 is an equidigital number, since it uses as much as digits as its factorization.

7168921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 34.

The square root of 7168921 is about 2677.4840802515. The cubic root of 7168921 is about 192.8196387455.

The spelling of 7168921 in words is "seven million, one hundred sixty-eight thousand, nine hundred twenty-one".