20405166666 has 16 divisors (see below), whose sum is σ = 40815881184. Its totient is φ = 6800797584.

The previous prime is 20405166629. The next prime is 20405166689. The reversal of 20405166666 is 66666150402.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 182560 + ... + 272283.

It is an arithmetic number, because the mean of its divisors is an integer number (2550992574).

Almost surely, 2^20405166666 is an apocalyptic number.

20405166666 is an abundant number, since it is smaller than the sum of its proper divisors (20410714518).

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

20405166666 is a wasteful number, since it uses less digits than its factorization.

20405166666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462325.

The product of its (nonzero) digits is 311040, while the sum is 42.

The spelling of 20405166666 in words is "twenty billion, four hundred five million, one hundred sixty-six thousand, six hundred sixty-six".