21112106 has 4 divisors (see below), whose sum is σ = 31668162. Its totient is φ = 10556052.

The previous prime is 21112103. The next prime is 21112121. The reversal of 21112106 is 60121112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 16072081 + 5040025 = 4009^2 + 2245^2 .

It is not an unprimeable number, because it can be changed into a prime (21112103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5278025 + ... + 5278028.

Almost surely, 2^21112106 is an apocalyptic number.

21112106 is a deficient number, since it is larger than the sum of its proper divisors (10556056).

21112106 is a wasteful number, since it uses less digits than its factorization.

21112106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10556055.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 21112106 is about 4594.7911813270. The cubic root of 21112106 is about 276.3824862214.

Adding to 21112106 its reverse (60121112), we get a palindrome (81233218).

The spelling of 21112106 in words is "twenty-one million, one hundred twelve thousand, one hundred six".