21364448 has 48 divisors (see below), whose sum is σ = 48513024. Its totient is φ = 9072000.

The previous prime is 21364433. The next prime is 21364451. The reversal of 21364448 is 84446312.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (32).

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, 28073 + ... + 28823.

It is an arithmetic number, because the mean of its divisors is an integer number (1010688).

Almost surely, 2^21364448 is an apocalyptic number.

21364448 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21364448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24256512).

21364448 is an abundant number, since it is smaller than the sum of its proper divisors (27148576).

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

21364448 is a wasteful number, since it uses less digits than its factorization.

21364448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 895 (or 887 counting only the distinct ones).

The product of its digits is 18432, while the sum is 32.

The square root of 21364448 is about 4622.1691877299. The cubic root of 21364448 is about 277.4792798965.

It can be divided in two parts, 21364 and 448, that added together give a palindrome (21812).

The spelling of 21364448 in words is "twenty-one million, three hundred sixty-four thousand, four hundred forty-eight".