66640533504666 has 64 divisors (see below), whose sum is σ = 147696570878976. Its totient is φ = 19875758604800.

The previous prime is 66640533504563. The next prime is 66640533504679.

66640533504666 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9362775 + ... + 14864138.

It is an arithmetic number, because the mean of its divisors is an integer number (2307758919984).

Almost surely, 2^{66640533504666} is an apocalyptic number.

66640533504666 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

66640533504666 is an abundant number, since it is smaller than the sum of its proper divisors (81056037374310).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66640533504666 is a wasteful number, since it uses less digits than its factorization.

66640533504666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24227587.

The product of its (nonzero) digits is 167961600, while the sum is 60.

The spelling of 66640533504666 in words is "sixty-six trillion, six hundred forty billion, five hundred thirty-three million, five hundred four thousand, six hundred sixty-six".