66573979907 has 2 divisors, whose sum is σ = 66573979908. Its totient is φ = 66573979906.

The previous prime is 66573979873. The next prime is 66573979921. The reversal of 66573979907 is 70997937566.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66573979907 - 2²⁰ = 66572931331 is a prime.

It is not a weakly prime, because it can be changed into another prime (66573979607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33286989953 + 33286989954.

It is an arithmetic number, because the mean of its divisors is an integer number (33286989954).

Almost surely, 2^66573979907 is an apocalyptic number.

66573979907 is a deficient number, since it is larger than the sum of its proper divisors (1).

66573979907 is an equidigital number, since it uses as much as digits as its factorization.

66573979907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 135025380, while the sum is 68.

The spelling of 66573979907 in words is "sixty-six billion, five hundred seventy-three million, nine hundred seventy-nine thousand, nine hundred seven".