7929821321 has 2 divisors, whose sum is σ = 7929821322. Its totient is φ = 7929821320.

The previous prime is 7929821311. The next prime is 7929821329. The reversal of 7929821321 is 1231289297.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7099747600 + 830073721 = 84260^2 + 28811^2 .

It is a cyclic number.

It is not a de Polignac number, because 7929821321 - 2²⁶ = 7862712457 is a prime.

It is not a weakly prime, because it can be changed into another prime (7929821329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3964910660 + 3964910661.

It is an arithmetic number, because the mean of its divisors is an integer number (3964910661).

Almost surely, 2^7929821321 is an apocalyptic number.

It is an amenable number.

7929821321 is a deficient number, since it is larger than the sum of its proper divisors (1).

7929821321 is an equidigital number, since it uses as much as digits as its factorization.

7929821321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 44.

The square root of 7929821321 is about 89049.5441931063. The cubic root of 7929821321 is about 1994.1345920605.

The spelling of 7929821321 in words is "seven billion, nine hundred twenty-nine million, eight hundred twenty-one thousand, three hundred twenty-one".