66357566749 has 2 divisors, whose sum is σ = 66357566750. Its totient is φ = 66357566748.

The previous prime is 66357566719. The next prime is 66357566767. The reversal of 66357566749 is 94766575366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65750190724 + 607376025 = 256418^2 + 24645^2 .

It is a cyclic number.

It is not a de Polignac number, because 66357566749 - 2²³ = 66349178141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66357566719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33178783374 + 33178783375.

It is an arithmetic number, because the mean of its divisors is an integer number (33178783375).

Almost surely, 2^66357566749 is an apocalyptic number.

It is an amenable number.

66357566749 is a deficient number, since it is larger than the sum of its proper divisors (1).

66357566749 is an equidigital number, since it uses as much as digits as its factorization.

66357566749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 171460800, while the sum is 64.

The spelling of 66357566749 in words is "sixty-six billion, three hundred fifty-seven million, five hundred sixty-six thousand, seven hundred forty-nine".