21347208 has 24 divisors (see below), whose sum is σ = 57815550. Its totient is φ = 7115712.

The previous prime is 21347201. The next prime is 21347213. The reversal of 21347208 is 80274312.

It can be written as a sum of positive squares in only one way, i.e., 20088324 + 1258884 = 4482^2 + 1122^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (21347201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 148173 + ... + 148316.

Almost surely, 2^21347208 is an apocalyptic number.

It is an amenable number.

21347208 is an abundant number, since it is smaller than the sum of its proper divisors (36468342).

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

21347208 is a wasteful number, since it uses less digits than its factorization.

21347208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296501 (or 296494 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 21347208 is about 4620.3038861097. The cubic root of 21347208 is about 277.4046226887.

The spelling of 21347208 in words is "twenty-one million, three hundred forty-seven thousand, two hundred eight".