821981448 has 96 divisors (see below), whose sum is σ = 2290448160. Its totient is φ = 266146560.

The previous prime is 821981443. The next prime is 821981557. The reversal of 821981448 is 844189128.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (821981443) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 905811 + ... + 906717.

It is an arithmetic number, because the mean of its divisors is an integer number (23858835).

Almost surely, 2^821981448 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 821981448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1145224080).

821981448 is an abundant number, since it is smaller than the sum of its proper divisors (1468466712).

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

821981448 is a wasteful number, since it uses less digits than its factorization.

821981448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1267 (or 1260 counting only the distinct ones).

The product of its digits is 147456, while the sum is 45.

The square root of 821981448 is about 28670.2188341840. The cubic root of 821981448 is about 936.7434647556.

The spelling of 821981448 in words is "eight hundred twenty-one million, nine hundred eighty-one thousand, four hundred forty-eight".