81488209 has 8 divisors (see below), whose sum is σ = 89008128. Its totient is φ = 73986960.

The previous prime is 81488203. The next prime is 81488219. The reversal of 81488209 is 90288418.

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 81488209 - 2³ = 81488201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81488201) 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, 5424 + ... + 13870.

It is an arithmetic number, because the mean of its divisors is an integer number (11126016).

Almost surely, 2^81488209 is an apocalyptic number.

It is an amenable number.

81488209 is a deficient number, since it is larger than the sum of its proper divisors (7519919).

81488209 is a wasteful number, since it uses less digits than its factorization.

81488209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9335.

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 81488209 is about 9027.0819759211. The cubic root of 81488209 is about 433.5424134369.

The spelling of 81488209 in words is "eighty-one million, four hundred eighty-eight thousand, two hundred nine".