66669999777847 has 2 divisors, whose sum is σ = 66669999777848. Its totient is φ = 66669999777846.

The previous prime is 66669999777839. The next prime is 66669999777853. The reversal of 66669999777847 is 74877799996666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66669999777847 - 2³ = 66669999777839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66669999777947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33334999888923 + 33334999888924.

It is an arithmetic number, because the mean of its divisors is an integer number (33334999888924).

Almost surely, 2^{66669999777847} is an apocalyptic number.

66669999777847 is a deficient number, since it is larger than the sum of its proper divisors (1).

66669999777847 is an equidigital number, since it uses as much as digits as its factorization.

66669999777847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653306798592, while the sum is 100.

The spelling of 66669999777847 in words is "sixty-six trillion, six hundred sixty-nine billion, nine hundred ninety-nine million, seven hundred seventy-seven thousand, eight hundred forty-seven".