21988248 has 16 divisors (see below), whose sum is σ = 54970680. Its totient is φ = 7329408.

The previous prime is 21988247. The next prime is 21988279. The reversal of 21988248 is 84288912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21988247) 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, 458065 + ... + 458112.

Almost surely, 2^21988248 is an apocalyptic number.

It is an amenable number.

21988248 is an abundant number, since it is smaller than the sum of its proper divisors (32982432).

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

21988248 is a wasteful number, since it uses less digits than its factorization.

21988248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 916186 (or 916182 counting only the distinct ones).

The product of its digits is 73728, while the sum is 42.

The square root of 21988248 is about 4689.1628250680. The cubic root of 21988248 is about 280.1540308967.

The spelling of 21988248 in words is "twenty-one million, nine hundred eighty-eight thousand, two hundred forty-eight".