21201208 has 16 divisors (see below), whose sum is σ = 45431280. Its totient is φ = 9086208.

The previous prime is 21201203. The next prime is 21201209. The reversal of 21201208 is 80210212.

It is a junction number, because it is equal to n+sod(n) for n = 21201191 and 21201200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201203) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189241 + ... + 189352.

It is an arithmetic number, because the mean of its divisors is an integer number (2839455).

Almost surely, 2^21201208 is an apocalyptic number.

21201208 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21201208 is an abundant number, since it is smaller than the sum of its proper divisors (24230072).

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

21201208 is a wasteful number, since it uses less digits than its factorization.

21201208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378606 (or 378602 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 21201208 is about 4604.4769518372. The cubic root of 21201208 is about 276.7707574329.

The spelling of 21201208 in words is "twenty-one million, two hundred one thousand, two hundred eight".