66264643321 has 2 divisors, whose sum is σ = 66264643322. Its totient is φ = 66264643320.

The previous prime is 66264643301. The next prime is 66264643337. The reversal of 66264643321 is 12334646266.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66016108096 + 248535225 = 256936^2 + 15765^2 .

It is a cyclic number.

It is not a de Polignac number, because 66264643321 - 2²¹ = 66262546169 is a prime.

It is not a weakly prime, because it can be changed into another prime (66264643301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33132321660 + 33132321661.

It is an arithmetic number, because the mean of its divisors is an integer number (33132321661).

Almost surely, 2^66264643321 is an apocalyptic number.

It is an amenable number.

66264643321 is a deficient number, since it is larger than the sum of its proper divisors (1).

66264643321 is an equidigital number, since it uses as much as digits as its factorization.

66264643321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 746496, while the sum is 43.

The spelling of 66264643321 in words is "sixty-six billion, two hundred sixty-four million, six hundred forty-three thousand, three hundred twenty-one".