7720832321 has 2 divisors, whose sum is σ = 7720832322. Its totient is φ = 7720832320.

The previous prime is 7720832309. The next prime is 7720832323. The reversal of 7720832321 is 1232380277.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5919763600 + 1801068721 = 76940^2 + 42439^2 .

It is a cyclic number.

It is not a de Polignac number, because 7720832321 - 2¹⁰ = 7720831297 is a prime.

It is a super-2 number, since 2×7720832321² (a number of 21 digits) contains 22 as substring.

Together with 7720832323, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7720832323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3860416160 + 3860416161.

It is an arithmetic number, because the mean of its divisors is an integer number (3860416161).

Almost surely, 2^7720832321 is an apocalyptic number.

It is an amenable number.

7720832321 is a deficient number, since it is larger than the sum of its proper divisors (1).

7720832321 is an equidigital number, since it uses as much as digits as its factorization.

7720832321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224, while the sum is 35.

The square root of 7720832321 is about 87868.2668601128. The cubic root of 7720832321 is about 1976.4600491210.

The spelling of 7720832321 in words is "seven billion, seven hundred twenty million, eight hundred thirty-two thousand, three hundred twenty-one".