51660105666 has 64 divisors (see below), whose sum is σ = 115612963200. Its totient is φ = 15279538176.

The previous prime is 51660105659. The next prime is 51660105677. The reversal of 51660105666 is 66650106615.

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 31 ways as a sum of consecutive naturals, for example, 463170 + ... + 563778.

It is an arithmetic number, because the mean of its divisors is an integer number (1806452550).

Almost surely, 2^51660105666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51660105666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57806481600).

51660105666 is an abundant number, since it is smaller than the sum of its proper divisors (63952857534).

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

51660105666 is a wasteful number, since it uses less digits than its factorization.

51660105666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100883.

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 51660105666 in words is "fifty-one billion, six hundred sixty million, one hundred five thousand, six hundred sixty-six".