21214210 has 16 divisors (see below), whose sum is σ = 38756736. Its totient is φ = 8358768.

The previous prime is 21214187. The next prime is 21214229. The reversal of 21214210 is 1241212.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15162 + ... + 16501.

It is an arithmetic number, because the mean of its divisors is an integer number (2422296).

Almost surely, 2^21214210 is an apocalyptic number.

21214210 is a deficient number, since it is larger than the sum of its proper divisors (17542526).

21214210 is a wasteful number, since it uses less digits than its factorization.

21214210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31737.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 21214210 is about 4605.8886221879. Note that the first 3 decimals coincide. The cubic root of 21214210 is about 276.8273239897.

Adding to 21214210 its reverse (1241212), we get a palindrome (22455422).

The spelling of 21214210 in words is "twenty-one million, two hundred fourteen thousand, two hundred ten".