81920448 has 42 divisors (see below), whose sum is σ = 234811824. Its totient is φ = 27306624.

The previous prime is 81920429. The next prime is 81920459. The reversal of 81920448 is 84402918.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 70536 + ... + 71687.

Almost surely, 2^81920448 is an apocalyptic number.

It is an amenable number.

81920448 is an abundant number, since it is smaller than the sum of its proper divisors (152891376).

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

81920448 is a wasteful number, since it uses less digits than its factorization.

81920448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142241 (or 142228 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 81920448 is about 9050.9915478913. The cubic root of 81920448 is about 434.3076103589.

The spelling of 81920448 in words is "eighty-one million, nine hundred twenty thousand, four hundred forty-eight".