81528573 has 8 divisors (see below), whose sum is σ = 124234048. Its totient is φ = 46587744.

The previous prime is 81528571. The next prime is 81528581. The reversal of 81528573 is 37582518.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81528573 - 2¹ = 81528571 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81528571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1941136 + ... + 1941177.

It is an arithmetic number, because the mean of its divisors is an integer number (15529256).

Almost surely, 2^81528573 is an apocalyptic number.

It is an amenable number.

81528573 is a deficient number, since it is larger than the sum of its proper divisors (42705475).

81528573 is a wasteful number, since it uses less digits than its factorization.

81528573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3882323.

The product of its digits is 67200, while the sum is 39.

The square root of 81528573 is about 9029.3174160620. The cubic root of 81528573 is about 433.6139845988.

The spelling of 81528573 in words is "eighty-one million, five hundred twenty-eight thousand, five hundred seventy-three".