7656364021 has 2 divisors, whose sum is σ = 7656364022. Its totient is φ = 7656364020.

The previous prime is 7656364019. The next prime is 7656364031. The reversal of 7656364021 is 1204636567.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7159698225 + 496665796 = 84615^2 + 22286^2 .

It is a cyclic number.

It is not a de Polignac number, because 7656364021 - 2¹ = 7656364019 is a prime.

Together with 7656364019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7656364031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3828182010 + 3828182011.

It is an arithmetic number, because the mean of its divisors is an integer number (3828182011).

Almost surely, 2^7656364021 is an apocalyptic number.

It is an amenable number.

7656364021 is a deficient number, since it is larger than the sum of its proper divisors (1).

7656364021 is an equidigital number, since it uses as much as digits as its factorization.

7656364021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 40.

The square root of 7656364021 is about 87500.6515461456. The cubic root of 7656364021 is about 1970.9435747970.

The spelling of 7656364021 in words is "seven billion, six hundred fifty-six million, three hundred sixty-four thousand, twenty-one".