81541823 has 8 divisors (see below), whose sum is σ = 92022480. Its totient is φ = 71572480.

The previous prime is 81541807. The next prime is 81541829. The reversal of 81541823 is 32814518.

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

It is a cyclic number.

It is not a de Polignac number, because 81541823 - 2⁴ = 81541807 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81541823.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81541829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127490 + ... + 128127.

It is an arithmetic number, because the mean of its divisors is an integer number (11502810).

Almost surely, 2^81541823 is an apocalyptic number.

81541823 is a deficient number, since it is larger than the sum of its proper divisors (10480657).

81541823 is a wasteful number, since it uses less digits than its factorization.

81541823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255657.

The product of its digits is 7680, while the sum is 32.

The square root of 81541823 is about 9030.0511072751. The cubic root of 81541823 is about 433.6374735993.

The spelling of 81541823 in words is "eighty-one million, five hundred forty-one thousand, eight hundred twenty-three".