81343242 has 36 divisors (see below), whose sum is σ = 181190646. Its totient is φ = 26373600.

The previous prime is 81343211. The next prime is 81343253. The reversal of 81343242 is 24234318.

81343242 is a `hidden beast` number, since 81 + 343 + 242 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 80622441 + 720801 = 8979^2 + 849^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 22992 + ... + 26292.

Almost surely, 2^81343242 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81343242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90595323).

81343242 is an abundant number, since it is smaller than the sum of its proper divisors (99847404).

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

81343242 is a wasteful number, since it uses less digits than its factorization.

81343242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3383 (or 3343 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 81343242 is about 9019.0488412027. The cubic root of 81343242 is about 433.2851711101.

The spelling of 81343242 in words is "eighty-one million, three hundred forty-three thousand, two hundred forty-two".