81295523 has 4 divisors (see below), whose sum is σ = 81353688. Its totient is φ = 81237360.

The previous prime is 81295517. The next prime is 81295541. The reversal of 81295523 is 32559218.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81295523 - 2¹⁶ = 81229987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81295553) 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 3 ways as a sum of consecutive naturals, for example, 26933 + ... + 29798.

It is an arithmetic number, because the mean of its divisors is an integer number (20338422).

Almost surely, 2^81295523 is an apocalyptic number.

81295523 is a deficient number, since it is larger than the sum of its proper divisors (58165).

81295523 is a wasteful number, since it uses less digits than its factorization.

81295523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58164.

The product of its digits is 21600, while the sum is 35.

The square root of 81295523 is about 9016.4029967610. The cubic root of 81295523 is about 433.2004274200.

It can be divided in two parts, 81295 and 523, that added together give a palindrome (81818).

The spelling of 81295523 in words is "eighty-one million, two hundred ninety-five thousand, five hundred twenty-three".