21050166 has 8 divisors (see below), whose sum is σ = 42100344. Its totient is φ = 7016720.

The previous prime is 21050149. The next prime is 21050171. The reversal of 21050166 is 66105012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

21050166 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1754175 + ... + 1754186.

It is an arithmetic number, because the mean of its divisors is an integer number (5262543).

Almost surely, 2^21050166 is an apocalyptic number.

21050166 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21050166 is a wasteful number, since it uses less digits than its factorization.

21050166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3508366.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 21050166 is about 4588.0459893074. The cubic root of 21050166 is about 276.1119321254. Note that the first 3 decimals are identical.

Adding to 21050166 its reverse (66105012), we get a palindrome (87155178).

The spelling of 21050166 in words is "twenty-one million, fifty thousand, one hundred sixty-six".