21470166 has 48 divisors (see below), whose sum is σ = 48597120. Its totient is φ = 6842880.

The previous prime is 21470149. The next prime is 21470219. The reversal of 21470166 is 66107412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60646 + ... + 60998.

It is an arithmetic number, because the mean of its divisors is an integer number (1012440).

Almost surely, 2^21470166 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21470166, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24298560).

21470166 is an abundant number, since it is smaller than the sum of its proper divisors (27126954).

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

21470166 is a wasteful number, since it uses less digits than its factorization.

21470166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501 (or 498 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21470166 is about 4633.5910479886. The cubic root of 21470166 is about 277.9362119230.

Adding to 21470166 its reverse (66107412), we get a palindrome (87577578).

The spelling of 21470166 in words is "twenty-one million, four hundred seventy thousand, one hundred sixty-six".