81588090 has 32 divisors (see below), whose sum is σ = 206118720. Its totient is φ = 20611584.

The previous prime is 81588053. The next prime is 81588097. The reversal of 81588090 is 9088518.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (81588097) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70999 + ... + 72138.

It is an arithmetic number, because the mean of its divisors is an integer number (6441210).

Almost surely, 2^81588090 is an apocalyptic number.

81588090 is an abundant number, since it is smaller than the sum of its proper divisors (124530630).

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

81588090 is a wasteful number, since it uses less digits than its factorization.

81588090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143166.

The product of its (nonzero) digits is 23040, while the sum is 39.

The square root of 81588090 is about 9032.6125788722. The cubic root of 81588090 is about 433.7194736937.

The spelling of 81588090 in words is "eighty-one million, five hundred eighty-eight thousand, ninety".