21150208 has 40 divisors (see below), whose sum is σ = 42781860. Its totient is φ = 10444800.

The previous prime is 21150203. The next prime is 21150209. The reversal of 21150208 is 80205112.

It can be written as a sum of positive squares in 2 ways, for example, as 15618304 + 5531904 = 3952^2 + 2352^2 .

It is not an unprimeable number, because it can be changed into a prime (21150203) 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, 51508 + ... + 51916.

Almost surely, 2^21150208 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 21150208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21390930).

21150208 is an abundant number, since it is smaller than the sum of its proper divisors (21631652).

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

21150208 is an equidigital number, since it uses as much as digits as its factorization.

21150208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528 (or 512 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 21150208 is about 4598.9355290110. The cubic root of 21150208 is about 276.5486530759.

The spelling of 21150208 in words is "twenty-one million, one hundred fifty thousand, two hundred eight".