21442106 has 12 divisors (see below), whose sum is σ = 37414458. Its totient is φ = 9189432.

The previous prime is 21442103. The next prime is 21442133. The reversal of 21442106 is 60124412.

It can be written as a sum of positive squares in only one way, i.e., 16883881 + 4558225 = 4109^2 + 2135^2 .

It is not an unprimeable number, because it can be changed into a prime (21442103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 109301 + ... + 109496.

Almost surely, 2^21442106 is an apocalyptic number.

21442106 is a deficient number, since it is larger than the sum of its proper divisors (15972352).

21442106 is a wasteful number, since it uses less digits than its factorization.

21442106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218813 (or 218806 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 21442106 is about 4630.5621688948. The cubic root of 21442106 is about 277.8150780962.

Adding to 21442106 its reverse (60124412), we get a palindrome (81566518).

The spelling of 21442106 in words is "twenty-one million, four hundred forty-two thousand, one hundred six".