21658682 has 4 divisors (see below), whose sum is σ = 32488026. Its totient is φ = 10829340.

The previous prime is 21658673. The next prime is 21658691. The reversal of 21658682 is 28685612.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21658673) and next prime (21658691).

It can be written as a sum of positive squares in only one way, i.e., 21446161 + 212521 = 4631^2 + 461^2 .

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, 5414669 + ... + 5414672.

Almost surely, 2^21658682 is an apocalyptic number.

21658682 is a deficient number, since it is larger than the sum of its proper divisors (10829344).

21658682 is a wasteful number, since it uses less digits than its factorization.

21658682 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10829343.

The product of its digits is 46080, while the sum is 38.

The square root of 21658682 is about 4653.8889114374. Note that the first 3 decimals coincide. The cubic root of 21658682 is about 278.7473035593.

The spelling of 21658682 in words is "twenty-one million, six hundred fifty-eight thousand, six hundred eighty-two".