661166166115 has 48 divisors (see below), whose sum is σ = 984595046400. Its totient is φ = 417329318016.

The previous prime is 661166166061. The next prime is 661166166121. The reversal of 661166166115 is 511661661166.

It is not a de Polignac number, because 661166166115 - 2⁹ = 661166165603 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1967806 + ... + 2279164.

It is an arithmetic number, because the mean of its divisors is an integer number (20512396800).

Almost surely, 2^661166166115 is an apocalyptic number.

661166166115 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

661166166115 is a deficient number, since it is larger than the sum of its proper divisors (323428880285).

661166166115 is a wasteful number, since it uses less digits than its factorization.

661166166115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311756 (or 311743 counting only the distinct ones).

The product of its digits is 233280, while the sum is 46.

The spelling of 661166166115 in words is "six hundred sixty-one billion, one hundred sixty-six million, one hundred sixty-six thousand, one hundred fifteen".