21086208 has 180 divisors, whose sum is σ = 71563128. Its totient is φ = 5898240.

The previous prime is 21086203. The next prime is 21086227. The reversal of 21086208 is 80268012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21086201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1622010 + ... + 1622022.

Almost surely, 2^21086208 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21086208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35781564).

21086208 is an abundant number, since it is smaller than the sum of its proper divisors (50476920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21086208 is a wasteful number, since it uses less digits than its factorization.

21086208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58 (or 29 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 21086208 is about 4591.9721253509. The cubic root of 21086208 is about 276.2694281430.

The spelling of 21086208 in words is "twenty-one million, eighty-six thousand, two hundred eight".