81840756458 has 8 divisors (see below), whose sum is σ = 125616044928. Its totient is φ = 39968741484.

The previous prime is 81840756407. The next prime is 81840756463. The reversal of 81840756458 is 85465704818.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 475818266 + ... + 475818437.

It is an arithmetic number, because the mean of its divisors is an integer number (15702005616).

Almost surely, 2^81840756458 is an apocalyptic number.

81840756458 is a deficient number, since it is larger than the sum of its proper divisors (43775288470).

81840756458 is a wasteful number, since it uses less digits than its factorization.

81840756458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 951636748.

The product of its (nonzero) digits is 8601600, while the sum is 56.

The spelling of 81840756458 in words is "eighty-one billion, eight hundred forty million, seven hundred fifty-six thousand, four hundred fifty-eight".