21102682 has 4 divisors (see below), whose sum is σ = 31654026. Its totient is φ = 10551340.

The previous prime is 21102677. The next prime is 21102709. The reversal of 21102682 is 28620112.

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., 11498881 + 9603801 = 3391^2 + 3099^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5275669 + ... + 5275672.

Almost surely, 2^21102682 is an apocalyptic number.

21102682 is a deficient number, since it is larger than the sum of its proper divisors (10551344).

21102682 is a wasteful number, since it uses less digits than its factorization.

21102682 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10551343.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 21102682 is about 4593.7655577968. The cubic root of 21102682 is about 276.3413563250.

Adding to 21102682 its reverse (28620112), we get a palindrome (49722794).

The spelling of 21102682 in words is "twenty-one million, one hundred two thousand, six hundred eighty-two".