81485999 has 4 divisors (see below), whose sum is σ = 93126864. Its totient is φ = 69845136.

The previous prime is 81485959. The next prime is 81486017. The reversal of 81485999 is 99958418.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81485999 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81485999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81485939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5820422 + ... + 5820435.

It is an arithmetic number, because the mean of its divisors is an integer number (23281716).

Almost surely, 2^81485999 is an apocalyptic number.

81485999 is a deficient number, since it is larger than the sum of its proper divisors (11640865).

81485999 is a wasteful number, since it uses less digits than its factorization.

81485999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11640864.

The product of its digits is 933120, while the sum is 53.

The square root of 81485999 is about 9026.9595656566. The cubic root of 81485999 is about 433.5384941075.

The spelling of 81485999 in words is "eighty-one million, four hundred eighty-five thousand, nine hundred ninety-nine".