21470208 has 88 divisors (see below), whose sum is σ = 59444880. Its totient is φ = 6881280.

The previous prime is 21470149. The next prime is 21470219. The reversal of 21470208 is 80207412.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 88968 + ... + 89208.

It is an arithmetic number, because the mean of its divisors is an integer number (675510).

Almost surely, 2^21470208 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 21470208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29722440).

21470208 is an abundant number, since it is smaller than the sum of its proper divisors (37974672).

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

21470208 is a wasteful number, since it uses less digits than its factorization.

21470208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293 (or 275 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 21470208 is about 4633.5955801084. The cubic root of 21470208 is about 277.9363931561.

The spelling of 21470208 in words is "twenty-one million, four hundred seventy thousand, two hundred eight".