81530776 has 16 divisors (see below), whose sum is σ = 161862840. Its totient is φ = 38367360.

The previous prime is 81530753. The next prime is 81530809. The reversal of 81530776 is 67703518.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 299610 + ... + 299881.

Almost surely, 2^81530776 is an apocalyptic number.

It is an amenable number.

81530776 is a deficient number, since it is larger than the sum of its proper divisors (80332064).

81530776 is a wasteful number, since it uses less digits than its factorization.

81530776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599514 (or 599510 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 37.

The square root of 81530776 is about 9029.4394067406. The cubic root of 81530776 is about 433.6178901539.

The spelling of 81530776 in words is "eighty-one million, five hundred thirty thousand, seven hundred seventy-six".