81408588 has 12 divisors (see below), whose sum is σ = 189953400. Its totient is φ = 27136192.

The previous prime is 81408581. The next prime is 81408601. The reversal of 81408588 is 88580418.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (81408581) 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, 3392013 + ... + 3392036.

It is an arithmetic number, because the mean of its divisors is an integer number (15829450).

Almost surely, 2^81408588 is an apocalyptic number.

It is an amenable number.

81408588 is an abundant number, since it is smaller than the sum of its proper divisors (108544812).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81408588 is a wasteful number, since it uses less digits than its factorization.

81408588 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6784056 (or 6784054 counting only the distinct ones).

The product of its (nonzero) digits is 81920, while the sum is 42.

The square root of 81408588 is about 9022.6707797636. The cubic root of 81408588 is about 433.4011646610.

The spelling of 81408588 in words is "eighty-one million, four hundred eight thousand, five hundred eighty-eight".