21241208 has 8 divisors (see below), whose sum is σ = 39827280. Its totient is φ = 10620600.

The previous prime is 21241163. The next prime is 21241217. The reversal of 21241208 is 80214212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 21241208.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1327568 + ... + 1327583.

It is an arithmetic number, because the mean of its divisors is an integer number (4978410).

Almost surely, 2^21241208 is an apocalyptic number.

It is an amenable number.

21241208 is a deficient number, since it is larger than the sum of its proper divisors (18586072).

21241208 is a wasteful number, since it uses less digits than its factorization.

21241208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2655157 (or 2655153 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 21241208 is about 4608.8185036948. The cubic root of 21241208 is about 276.9447078228.

The spelling of 21241208 in words is "twenty-one million, two hundred forty-one thousand, two hundred eight".