21116834 has 4 divisors (see below), whose sum is σ = 31675254. Its totient is φ = 10558416.

The previous prime is 21116831. The next prime is 21116857. The reversal of 21116834 is 43861112.

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., 21114025 + 2809 = 4595^2 + 53^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21116831) 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, 5279207 + ... + 5279210.

Almost surely, 2^21116834 is an apocalyptic number.

21116834 is a deficient number, since it is larger than the sum of its proper divisors (10558420).

21116834 is a wasteful number, since it uses less digits than its factorization.

21116834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10558419.

The product of its digits is 1152, while the sum is 26.

The square root of 21116834 is about 4595.3056481588. The cubic root of 21116834 is about 276.4031163890.

Adding to 21116834 its reverse (43861112), we get a palindrome (64977946).

The spelling of 21116834 in words is "twenty-one million, one hundred sixteen thousand, eight hundred thirty-four".