7221940309 has 2 divisors, whose sum is σ = 7221940310. Its totient is φ = 7221940308.

The previous prime is 7221940301. The next prime is 7221940331. The reversal of 7221940309 is 9030491227.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5636706084 + 1585234225 = 75078^2 + 39815^2 .

It is a cyclic number.

It is not a de Polignac number, because 7221940309 - 2³ = 7221940301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7221940301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3610970154 + 3610970155.

It is an arithmetic number, because the mean of its divisors is an integer number (3610970155).

Almost surely, 2^7221940309 is an apocalyptic number.

It is an amenable number.

7221940309 is a deficient number, since it is larger than the sum of its proper divisors (1).

7221940309 is an equidigital number, since it uses as much as digits as its factorization.

7221940309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 7221940309 is about 84981.9999117460. Note that the first 4 decimals coincide. The cubic root of 7221940309 is about 1932.9381817030.

The spelling of 7221940309 in words is "seven billion, two hundred twenty-one million, nine hundred forty thousand, three hundred nine".