21051106 has 4 divisors (see below), whose sum is σ = 31576662. Its totient is φ = 10525552.

The previous prime is 21051103. The next prime is 21051137. The reversal of 21051106 is 60115012.

It is a happy number.

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., 18020025 + 3031081 = 4245^2 + 1741^2 .

It is a super-3 number, since 3×21051106³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21051106.

It is not an unprimeable number, because it can be changed into a prime (21051101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5262775 + ... + 5262778.

Almost surely, 2^21051106 is an apocalyptic number.

21051106 is a deficient number, since it is larger than the sum of its proper divisors (10525556).

21051106 is a wasteful number, since it uses less digits than its factorization.

21051106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10525555.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 21051106 is about 4588.1484282878. The cubic root of 21051106 is about 276.1160420115.

Adding to 21051106 its reverse (60115012), we get a palindrome (81166118).

The spelling of 21051106 in words is "twenty-one million, fifty-one thousand, one hundred six".