81280384 has 16 divisors (see below), whose sum is σ = 161926020. Its totient is φ = 40640128.

The previous prime is 81280373. The next prime is 81280421. The reversal of 81280384 is 48308218.

81280384 is nontrivially palindromic in base 14.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 317374 + ... + 317629.

Almost surely, 2^81280384 is an apocalyptic number.

It is an amenable number.

81280384 is a deficient number, since it is larger than the sum of its proper divisors (80645636).

81280384 is an equidigital number, since it uses as much as digits as its factorization.

81280384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635017 (or 635005 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 34.

The square root of 81280384 is about 9015.5634321988. The cubic root of 81280384 is about 433.1735352937.

The spelling of 81280384 in words is "eighty-one million, two hundred eighty thousand, three hundred eighty-four".