21383248 has 10 divisors (see below), whose sum is σ = 41430074. Its totient is φ = 10691616.

The previous prime is 21383239. The next prime is 21383249. The reversal of 21383248 is 84238312.

It can be written as a sum of positive squares in only one way, i.e., 15272464 + 6110784 = 3908^2 + 2472^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21383249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 668211 + ... + 668242.

Almost surely, 2^21383248 is an apocalyptic number.

It is an amenable number.

21383248 is a deficient number, since it is larger than the sum of its proper divisors (20046826).

21383248 is a wasteful number, since it uses less digits than its factorization.

21383248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1336461 (or 1336455 counting only the distinct ones).

The product of its digits is 9216, while the sum is 31.

The square root of 21383248 is about 4624.2024177149. The cubic root of 21383248 is about 277.5606468644.

The spelling of 21383248 in words is "twenty-one million, three hundred eighty-three thousand, two hundred forty-eight".