81128374 has 8 divisors (see below), whose sum is σ = 122498928. Its totient is φ = 40295400.

The previous prime is 81128329. The next prime is 81128387. The reversal of 81128374 is 47382118.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 134017 + ... + 134620.

It is an arithmetic number, because the mean of its divisors is an integer number (15312366).

Almost surely, 2^81128374 is an apocalyptic number.

81128374 is a deficient number, since it is larger than the sum of its proper divisors (41370554).

81128374 is a wasteful number, since it uses less digits than its factorization.

81128374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268790.

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

The square root of 81128374 is about 9007.1290653571. The cubic root of 81128374 is about 432.9033274147.

The spelling of 81128374 in words is "eighty-one million, one hundred twenty-eight thousand, three hundred seventy-four".