81243178 has 8 divisors (see below), whose sum is σ = 122351040. Its totient is φ = 40459500.

The previous prime is 81243167. The next prime is 81243179. The reversal of 81243178 is 87134218.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (81243179) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 80418 + ... + 81421.

It is an arithmetic number, because the mean of its divisors is an integer number (15293880).

Almost surely, 2^81243178 is an apocalyptic number.

81243178 is a deficient number, since it is larger than the sum of its proper divisors (41107862).

81243178 is a wasteful number, since it uses less digits than its factorization.

81243178 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162092.

The product of its digits is 10752, while the sum is 34.

The square root of 81243178 is about 9013.4997642425. The cubic root of 81243178 is about 433.1074303144.

The spelling of 81243178 in words is "eighty-one million, two hundred forty-three thousand, one hundred seventy-eight".