21230208 has 64 divisors (see below), whose sum is σ = 62668800. Its totient is φ = 7075584.

The previous prime is 21230203. The next prime is 21230213. The reversal of 21230208 is 80203212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21230203) and next prime (21230213).

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21230203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 385 + ... + 6527.

It is an arithmetic number, because the mean of its divisors is an integer number (979200).

Almost surely, 2^21230208 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 21230208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31334400).

21230208 is an abundant number, since it is smaller than the sum of its proper divisors (41438592).

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

21230208 is an equidigital number, since it uses as much as digits as its factorization.

21230208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6166 (or 6148 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 21230208 is about 4607.6249847400. The cubic root of 21230208 is about 276.8968932509.

The spelling of 21230208 in words is "twenty-one million, two hundred thirty thousand, two hundred eight".