66813549041 has 2 divisors, whose sum is σ = 66813549042. Its totient is φ = 66813549040.

The previous prime is 66813548969. The next prime is 66813549059. The reversal of 66813549041 is 14094531866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48354250816 + 18459298225 = 219896^2 + 135865^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66813549041 is a prime.

It is a super-2 number, since 2×66813549041² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66813549541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33406774520 + 33406774521.

It is an arithmetic number, because the mean of its divisors is an integer number (33406774521).

Almost surely, 2^66813549041 is an apocalyptic number.

It is an amenable number.

66813549041 is a deficient number, since it is larger than the sum of its proper divisors (1).

66813549041 is an equidigital number, since it uses as much as digits as its factorization.

66813549041 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 47.

The spelling of 66813549041 in words is "sixty-six billion, eight hundred thirteen million, five hundred forty-nine thousand, forty-one".