81028585 has 8 divisors (see below), whose sum is σ = 106073856. Its totient is φ = 58929840.

The previous prime is 81028583. The next prime is 81028601. The reversal of 81028585 is 58582018.

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

It is not a de Polignac number, because 81028585 - 2¹ = 81028583 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81028583) 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, 736569 + ... + 736678.

It is an arithmetic number, because the mean of its divisors is an integer number (13259232).

Almost surely, 2^81028585 is an apocalyptic number.

It is an amenable number.

81028585 is a deficient number, since it is larger than the sum of its proper divisors (25045271).

81028585 is a wasteful number, since it uses less digits than its factorization.

81028585 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1473263.

The product of its (nonzero) digits is 25600, while the sum is 37.

The square root of 81028585 is about 9001.5879154736. The cubic root of 81028585 is about 432.7257622716.

The spelling of 81028585 in words is "eighty-one million, twenty-eight thousand, five hundred eighty-five".