7297921 has 2 divisors, whose sum is σ = 7297922. Its totient is φ = 7297920.

The previous prime is 7297897. The next prime is 7297931. The reversal of 7297921 is 1297927.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7290000 + 7921 = 2700^2 + 89^2 .

It is an emirp because it is prime and its reverse (1297927) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7297921 - 2⁵ = 7297889 is a prime.

It is not a weakly prime, because it can be changed into another prime (7297931) 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, 3648960 + 3648961.

It is an arithmetic number, because the mean of its divisors is an integer number (3648961).

Almost surely, 2^7297921 is an apocalyptic number.

It is an amenable number.

7297921 is a deficient number, since it is larger than the sum of its proper divisors (1).

7297921 is an equidigital number, since it uses as much as digits as its factorization.

7297921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15876, while the sum is 37.

The square root of 7297921 is about 2701.4664536137. The cubic root of 7297921 is about 193.9693241609.

It can be divided in two parts, 729 and 7921, that multiplied together give a square (5774409 = 2403²).

The spelling of 7297921 in words is "seven million, two hundred ninety-seven thousand, nine hundred twenty-one".