21166682 has 4 divisors (see below), whose sum is σ = 31750026. Its totient is φ = 10583340.

The previous prime is 21166679. The next prime is 21166711. The reversal of 21166682 is 28666112.

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., 21077281 + 89401 = 4591^2 + 299^2 .

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 as a sum of consecutive naturals, namely, 5291669 + ... + 5291672.

Almost surely, 2^21166682 is an apocalyptic number.

21166682 is a deficient number, since it is larger than the sum of its proper divisors (10583344).

21166682 is a wasteful number, since it uses less digits than its factorization.

21166682 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10583343.

The product of its digits is 6912, while the sum is 32.

The square root of 21166682 is about 4600.7262470180. The cubic root of 21166682 is about 276.6204361392.

The spelling of 21166682 in words is "twenty-one million, one hundred sixty-six thousand, six hundred eighty-two".