7315152721 has 2 divisors, whose sum is σ = 7315152722. Its totient is φ = 7315152720.

The previous prime is 7315152707. The next prime is 7315152769. The reversal of 7315152721 is 1272515137.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4741011025 + 2574141696 = 68855^2 + 50736^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7315152721 is a prime.

It is a super-3 number, since 3×7315152721³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (7315152781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3657576360 + 3657576361.

It is an arithmetic number, because the mean of its divisors is an integer number (3657576361).

Almost surely, 2^7315152721 is an apocalyptic number.

It is an amenable number.

7315152721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7315152721 is an equidigital number, since it uses as much as digits as its factorization.

7315152721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14700, while the sum is 34.

The square root of 7315152721 is about 85528.6660775205. Note that the first 3 decimals coincide. The cubic root of 7315152721 is about 1941.2186979826.

Adding to 7315152721 its reverse (1272515137), we get a palindrome (8587667858).

The spelling of 7315152721 in words is "seven billion, three hundred fifteen million, one hundred fifty-two thousand, seven hundred twenty-one".