81181296 has 60 divisors (see below), whose sum is σ = 259654512. Its totient is φ = 23194368.

The previous prime is 81181279. The next prime is 81181297. The reversal of 81181296 is 69218118.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 81181296.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81181297) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39261 + ... + 41276.

Almost surely, 2^81181296 is an apocalyptic number.

It is an amenable number.

81181296 is an abundant number, since it is smaller than the sum of its proper divisors (178473216).

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

81181296 is a wasteful number, since it uses less digits than its factorization.

81181296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80558 (or 80549 counting only the distinct ones).

The product of its digits is 6912, while the sum is 36.

The square root of 81181296 is about 9010.0663704548. The cubic root of 81181296 is about 432.9974380568.

The spelling of 81181296 in words is "eighty-one million, one hundred eighty-one thousand, two hundred ninety-six".