21166106346 has 144 divisors (see below), whose sum is σ = 58743753120. Its totient is φ = 5446042560.

The previous prime is 21166106323. The next prime is 21166106371. The reversal of 21166106346 is 64360166112.

It is a happy number.

21166106346 is a `hidden beast` number, since 2 + 1 + 1 + 6 + 6 + 10 + 634 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21166106346.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1027920 + ... + 1048308.

It is an arithmetic number, because the mean of its divisors is an integer number (407942730).

Almost surely, 2^21166106346 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21166106346, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29371876560).

21166106346 is an abundant number, since it is smaller than the sum of its proper divisors (37577646774).

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

21166106346 is a wasteful number, since it uses less digits than its factorization.

21166106346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20529 (or 20519 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The spelling of 21166106346 in words is "twenty-one billion, one hundred sixty-six million, one hundred six thousand, three hundred forty-six".