81335296 has 66 divisors (see below), whose sum is σ = 189253338. Its totient is φ = 34836480.

The previous prime is 81335251. The next prime is 81335297. The reversal of 81335296 is 69253318.

It can be written as a sum of positive squares in only one way, i.e., 76317696 + 5017600 = 8736^2 + 2240^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81335297) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 49366 + ... + 50986.

Almost surely, 2^81335296 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81335296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94626669).

81335296 is an abundant number, since it is smaller than the sum of its proper divisors (107918042).

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

81335296 is a wasteful number, since it uses less digits than its factorization.

81335296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1655 (or 1630 counting only the distinct ones).

The product of its digits is 38880, while the sum is 37.

The square root of 81335296 is about 9018.6083183604. The cubic root of 81335296 is about 433.2710621893.

The spelling of 81335296 in words is "eighty-one million, three hundred thirty-five thousand, two hundred ninety-six".