66666669999999 has 16 divisors (see below), whose sum is σ = 89280017856000. Its totient is φ = 44248964424896.

The previous prime is 66666669999971. The next prime is 66666670000033. The reversal of 66666669999999 is 99999996666666.

It is a cyclic number.

It is not a de Polignac number, because 66666669999999 - 2⁹ = 66666669999487 is a prime.

It is a super-5 number, since 5×66666669999999⁵ (a number of 70 digits) contains 55555 as substring.

66666669999999 is a strobogrammatic number because it is the same when read upside-down.

66666669999999 is a modest number, since divided by 9999999 gives 6666666 as remainder.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 66666669999897 and 66666669999906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66666669999929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6666669 + ... + 13333334.

It is an arithmetic number, because the mean of its divisors is an integer number (5580001116000).

Almost surely, 2^{66666669999999} is an apocalyptic number.

66666669999999 is a deficient number, since it is larger than the sum of its proper divisors (22613347856001).

66666669999999 is a wasteful number, since it uses less digits than its factorization.

66666669999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20004894.

The product of its digits is 1338925209984, while the sum is 105.

The spelling of 66666669999999 in words is "sixty-six trillion, six hundred sixty-six billion, six hundred sixty-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".