81580328 has 16 divisors (see below), whose sum is σ = 153758580. Its totient is φ = 40578048.

The previous prime is 81580309. The next prime is 81580361. The reversal of 81580328 is 82308518.

It can be written as a sum of positive squares in 2 ways, for example, as 62378404 + 19201924 = 7898^2 + 4382^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24875 + ... + 27962.

Almost surely, 2^81580328 is an apocalyptic number.

It is an amenable number.

81580328 is a deficient number, since it is larger than the sum of its proper divisors (72178252).

81580328 is a wasteful number, since it uses less digits than its factorization.

81580328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53036 (or 53032 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 81580328 is about 9032.1829033739. The cubic root of 81580328 is about 433.7057190827.

The spelling of 81580328 in words is "eighty-one million, five hundred eighty thousand, three hundred twenty-eight".