81243588 has 24 divisors (see below), whose sum is σ = 190536192. Its totient is φ = 26942944.

The previous prime is 81243581. The next prime is 81243607. The reversal of 81243588 is 88534218.

It is a super-2 number, since 2×81243588² = 13201041182227488, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81243581) 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, 14820 + ... + 19547.

It is an arithmetic number, because the mean of its divisors is an integer number (7939008).

Almost surely, 2^81243588 is an apocalyptic number.

It is an amenable number.

81243588 is an abundant number, since it is smaller than the sum of its proper divisors (109292604).

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

81243588 is a wasteful number, since it uses less digits than its factorization.

81243588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34571 (or 34569 counting only the distinct ones).

The product of its digits is 61440, while the sum is 39.

The square root of 81243588 is about 9013.5225078767. The cubic root of 81243588 is about 433.1081588833.

The spelling of 81243588 in words is "eighty-one million, two hundred forty-three thousand, five hundred eighty-eight".