81582465 has 8 divisors (see below), whose sum is σ = 130531968. Its totient is φ = 43510640.

The previous prime is 81582463. The next prime is 81582469. The reversal of 81582465 is 56428518.

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

It is not a de Polignac number, because 81582465 - 2¹ = 81582463 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81582461) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2719401 + ... + 2719430.

It is an arithmetic number, because the mean of its divisors is an integer number (16316496).

Almost surely, 2^81582465 is an apocalyptic number.

It is an amenable number.

81582465 is a deficient number, since it is larger than the sum of its proper divisors (48949503).

81582465 is a wasteful number, since it uses less digits than its factorization.

81582465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5438839.

The product of its digits is 76800, while the sum is 39.

The square root of 81582465 is about 9032.3012017979. The cubic root of 81582465 is about 433.7095060293.

The spelling of 81582465 in words is "eighty-one million, five hundred eighty-two thousand, four hundred sixty-five".