64771718321 has 2 divisors, whose sum is σ = 64771718322. Its totient is φ = 64771718320.

The previous prime is 64771718317. The next prime is 64771718359. The reversal of 64771718321 is 12381717746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62180908321 + 2590810000 = 249361^2 + 50900^2 .

It is a cyclic number.

It is not a de Polignac number, because 64771718321 - 2² = 64771718317 is a prime.

It is not a weakly prime, because it can be changed into another prime (64771712321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32385859160 + 32385859161.

It is an arithmetic number, because the mean of its divisors is an integer number (32385859161).

Almost surely, 2^64771718321 is an apocalyptic number.

It is an amenable number.

64771718321 is a deficient number, since it is larger than the sum of its proper divisors (1).

64771718321 is an equidigital number, since it uses as much as digits as its factorization.

64771718321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 395136, while the sum is 47.

The spelling of 64771718321 in words is "sixty-four billion, seven hundred seventy-one million, seven hundred eighteen thousand, three hundred twenty-one".