7117921 has 2 divisors, whose sum is σ = 7117922. Its totient is φ = 7117920.

The previous prime is 7117897. The next prime is 7117927. The reversal of 7117921 is 1297117.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7096896 + 21025 = 2664^2 + 145^2 .

It is a cyclic number.

It is not a de Polignac number, because 7117921 - 2⁵ = 7117889 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7117921.

It is not a weakly prime, because it can be changed into another prime (7117927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3558960 + 3558961.

It is an arithmetic number, because the mean of its divisors is an integer number (3558961).

Almost surely, 2^7117921 is an apocalyptic number.

It is an amenable number.

7117921 is a deficient number, since it is larger than the sum of its proper divisors (1).

7117921 is an equidigital number, since it uses as much as digits as its factorization.

7117921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 882, while the sum is 28.

The square root of 7117921 is about 2667.9432152878. The cubic root of 7117921 is about 192.3613078690.

The spelling of 7117921 in words is "seven million, one hundred seventeen thousand, nine hundred twenty-one".