21458448 has 240 divisors, whose sum is σ = 74280960. Its totient is φ = 5702400.

The previous prime is 21458443. The next prime is 21458449. The reversal of 21458448 is 84485412.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21458443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 692193 + ... + 692223.

It is an arithmetic number, because the mean of its divisors is an integer number (309504).

Almost surely, 2^21458448 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21458448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37140480).

21458448 is an abundant number, since it is smaller than the sum of its proper divisors (52822512).

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

21458448 is a wasteful number, since it uses less digits than its factorization.

21458448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98 (or 89 counting only the distinct ones).

The product of its digits is 40960, while the sum is 36.

The square root of 21458448 is about 4632.3264133694. The cubic root of 21458448 is about 277.8856386575.

The spelling of 21458448 in words is "twenty-one million, four hundred fifty-eight thousand, four hundred forty-eight".