21258248 has 24 divisors (see below), whose sum is σ = 43814190. Its totient is φ = 9662400.

The previous prime is 21258199. The next prime is 21258253. The reversal of 21258248 is 84285212.

It can be written as a sum of positive squares in only one way, i.e., 15507844 + 5750404 = 3938^2 + 2398^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10013 + ... + 11948.

Almost surely, 2^21258248 is an apocalyptic number.

It is an amenable number.

21258248 is an abundant number, since it is smaller than the sum of its proper divisors (22555942).

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

21258248 is a wasteful number, since it uses less digits than its factorization.

21258248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21989 (or 21974 counting only the distinct ones).

The product of its digits is 10240, while the sum is 32.

The square root of 21258248 is about 4610.6667630615. Note that the first 3 decimals coincide. The cubic root of 21258248 is about 277.0187443601.

The spelling of 21258248 in words is "twenty-one million, two hundred fifty-eight thousand, two hundred forty-eight".