66642169379 has 2 divisors, whose sum is σ = 66642169380. Its totient is φ = 66642169378.

The previous prime is 66642169367. The next prime is 66642169397. The reversal of 66642169379 is 97396124666.

66642169379 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (66642169397) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66642169379 - 2²⁰ = 66641120803 is a prime.

It is not a weakly prime, because it can be changed into another prime (66642169309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33321084689 + 33321084690.

It is an arithmetic number, because the mean of its divisors is an integer number (33321084690).

Almost surely, 2^66642169379 is an apocalyptic number.

66642169379 is a deficient number, since it is larger than the sum of its proper divisors (1).

66642169379 is an equidigital number, since it uses as much as digits as its factorization.

66642169379 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17635968, while the sum is 59.

The spelling of 66642169379 in words is "sixty-six billion, six hundred forty-two million, one hundred sixty-nine thousand, three hundred seventy-nine".