66666605550499 has 32 divisors (see below), whose sum is σ = 72660411293184. Its totient is φ = 61001063988480.

The previous prime is 66666605550487. The next prime is 66666605550509. The reversal of 66666605550499 is 99405550666666.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 66666605550499 - 2⁷ = 66666605550371 is a prime.

It is a super-3 number, since 3×66666605550499³ (a number of 42 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66666605550469) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11685304 + ... + 16428010.

It is an arithmetic number, because the mean of its divisors is an integer number (2270637852912).

Almost surely, 2^{66666605550499} is an apocalyptic number.

66666605550499 is a deficient number, since it is larger than the sum of its proper divisors (5993805742685).

66666605550499 is a wasteful number, since it uses less digits than its factorization.

66666605550499 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4743067.

The product of its (nonzero) digits is 1889568000, while the sum is 73.

The spelling of 66666605550499 in words is "sixty-six trillion, six hundred sixty-six billion, six hundred five million, five hundred fifty thousand, four hundred ninety-nine".