65164646021 has 2 divisors, whose sum is σ = 65164646022. Its totient is φ = 65164646020.

The previous prime is 65164645999. The next prime is 65164646077. The reversal of 65164646021 is 12064646156.

65164646021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60777040900 + 4387605121 = 246530^2 + 66239^2 .

It is a cyclic number.

It is not a de Polignac number, because 65164646021 - 2³⁰ = 64090904197 is a prime.

It is a super-2 number, since 2×65164646021² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 65164646021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65164646081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32582323010 + 32582323011.

It is an arithmetic number, because the mean of its divisors is an integer number (32582323011).

Almost surely, 2^65164646021 is an apocalyptic number.

It is an amenable number.

65164646021 is a deficient number, since it is larger than the sum of its proper divisors (1).

65164646021 is an equidigital number, since it uses as much as digits as its factorization.

65164646021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 41.

The spelling of 65164646021 in words is "sixty-five billion, one hundred sixty-four million, six hundred forty-six thousand, twenty-one".