21166706 has 16 divisors (see below), whose sum is σ = 34976448. Its totient is φ = 9526800.

The previous prime is 21166679. The next prime is 21166711. The reversal of 21166706 is 60766112.

It is a Curzon number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2405 + ... + 6936.

It is an arithmetic number, because the mean of its divisors is an integer number (2186028).

Almost surely, 2^21166706 is an apocalyptic number.

21166706 is a deficient number, since it is larger than the sum of its proper divisors (13809742).

21166706 is a wasteful number, since it uses less digits than its factorization.

21166706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9457.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 21166706 is about 4600.7288553011. The cubic root of 21166706 is about 276.6205406885.

The spelling of 21166706 in words is "twenty-one million, one hundred sixty-six thousand, seven hundred six".