7959386921 has 2 divisors, whose sum is σ = 7959386922. Its totient is φ = 7959386920.

The previous prime is 7959386909. The next prime is 7959386999. The reversal of 7959386921 is 1296839597.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7651875625 + 307511296 = 87475^2 + 17536^2 .

It is an emirp because it is prime and its reverse (1296839597) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7959386921 - 2¹⁸ = 7959124777 is a prime.

It is not a weakly prime, because it can be changed into another prime (7959386021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3979693460 + 3979693461.

It is an arithmetic number, because the mean of its divisors is an integer number (3979693461).

Almost surely, 2^7959386921 is an apocalyptic number.

It is an amenable number.

7959386921 is a deficient number, since it is larger than the sum of its proper divisors (1).

7959386921 is an equidigital number, since it uses as much as digits as its factorization.

7959386921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7348320, while the sum is 59.

The square root of 7959386921 is about 89215.3962105196. The cubic root of 7959386921 is about 1996.6098333821.

The spelling of 7959386921 in words is "seven billion, nine hundred fifty-nine million, three hundred eighty-six thousand, nine hundred twenty-one".