81483509 has 8 divisors (see below), whose sum is σ = 84430680. Its totient is φ = 78575616.

The previous prime is 81483497. The next prime is 81483527. The reversal of 81483509 is 90538418.

It can be written as a sum of positive squares in 4 ways, for example, as 87025 + 81396484 = 295^2 + 9022^2 .

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 81483509 - 2⁸ = 81483253 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81483559) 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, 5564 + ... + 13925.

It is an arithmetic number, because the mean of its divisors is an integer number (10553835).

Almost surely, 2^81483509 is an apocalyptic number.

It is an amenable number.

81483509 is a deficient number, since it is larger than the sum of its proper divisors (2947171).

81483509 is a wasteful number, since it uses less digits than its factorization.

81483509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19639.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 81483509 is about 9026.8216444106. The cubic root of 81483509 is about 433.5340781266.

The spelling of 81483509 in words is "eighty-one million, four hundred eighty-three thousand, five hundred nine".