668832822521 has 2 divisors, whose sum is σ = 668832822522. Its totient is φ = 668832822520.

The previous prime is 668832822499. The next prime is 668832822577. The reversal of 668832822521 is 125228238866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 668574416896 + 258405625 = 817664^2 + 16075^2 .

It is a cyclic number.

It is not a de Polignac number, because 668832822521 - 2⁶ = 668832822457 is a prime.

It is not a weakly prime, because it can be changed into another prime (668832822221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334416411260 + 334416411261.

It is an arithmetic number, because the mean of its divisors is an integer number (334416411261).

Almost surely, 2^668832822521 is an apocalyptic number.

It is an amenable number.

668832822521 is a deficient number, since it is larger than the sum of its proper divisors (1).

668832822521 is an equidigital number, since it uses as much as digits as its factorization.

668832822521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4423680, while the sum is 53.

The spelling of 668832822521 in words is "six hundred sixty-eight billion, eight hundred thirty-two million, eight hundred twenty-two thousand, five hundred twenty-one".