66681570379 has 2 divisors, whose sum is σ = 66681570380. Its totient is φ = 66681570378.

The previous prime is 66681570269. The next prime is 66681570391. The reversal of 66681570379 is 97307518666.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66681570379 - 2²¹ = 66679473227 is a prime.

It is not a weakly prime, because it can be changed into another prime (66681570779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33340785189 + 33340785190.

It is an arithmetic number, because the mean of its divisors is an integer number (33340785190).

Almost surely, 2^66681570379 is an apocalyptic number.

66681570379 is a deficient number, since it is larger than the sum of its proper divisors (1).

66681570379 is an equidigital number, since it uses as much as digits as its factorization.

66681570379 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11430720, while the sum is 58.

The spelling of 66681570379 in words is "sixty-six billion, six hundred eighty-one million, five hundred seventy thousand, three hundred seventy-nine".