21222116 has 12 divisors (see below), whose sum is σ = 37693488. Its totient is φ = 10452552.

The previous prime is 21222043. The next prime is 21222143. The reversal of 21222116 is 61122212.

It is a junction number, because it is equal to n+sod(n) for n = 21222094 and 21222103.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39326 + ... + 39861.

It is an arithmetic number, because the mean of its divisors is an integer number (3141124).

Almost surely, 2^21222116 is an apocalyptic number.

It is an amenable number.

21222116 is a deficient number, since it is larger than the sum of its proper divisors (16471372).

21222116 is a wasteful number, since it uses less digits than its factorization.

21222116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79258 (or 79256 counting only the distinct ones).

The product of its digits is 96, while the sum is 17.

The square root of 21222116 is about 4606.7467913919. The cubic root of 21222116 is about 276.8617085681.

Adding to 21222116 its product of digits (96), we get a palindrome (21222212).

Adding to 21222116 its reverse (61122212), we get a palindrome (82344328).

The spelling of 21222116 in words is "twenty-one million, two hundred twenty-two thousand, one hundred sixteen".