81804243 has 8 divisors (see below), whose sum is σ = 110152656. Its totient is φ = 53996000.

The previous prime is 81804241. The next prime is 81804251. The reversal of 81804243 is 34240818.

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 81804243 - 2¹ = 81804241 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81804243.

It is not an unprimeable number, because it can be changed into a prime (81804241) 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, 134688 + ... + 135293.

It is an arithmetic number, because the mean of its divisors is an integer number (13769082).

Almost surely, 2^81804243 is an apocalyptic number.

81804243 is a deficient number, since it is larger than the sum of its proper divisors (28348413).

81804243 is a wasteful number, since it uses less digits than its factorization.

81804243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270085.

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 81804243 is about 9044.5698073485. The cubic root of 81804243 is about 434.1021565746.

The spelling of 81804243 in words is "eighty-one million, eight hundred four thousand, two hundred forty-three".