64512033021521 has 2 divisors, whose sum is σ = 64512033021522. Its totient is φ = 64512033021520.

The previous prime is 64512033021503. The next prime is 64512033021563. The reversal of 64512033021521 is 12512033021546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64171314490000 + 340718531521 = 8010700^2 + 583711^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64512033021521 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (64512033021571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32256016510760 + 32256016510761.

It is an arithmetic number, because the mean of its divisors is an integer number (32256016510761).

Almost surely, 2^{64512033021521} is an apocalyptic number.

It is an amenable number.

64512033021521 is a deficient number, since it is larger than the sum of its proper divisors (1).

64512033021521 is an equidigital number, since it uses as much as digits as its factorization.

64512033021521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43200, while the sum is 35.

The spelling of 64512033021521 in words is "sixty-four trillion, five hundred twelve billion, thirty-three million, twenty-one thousand, five hundred twenty-one".