81756832371 has 8 divisors (see below), whose sum is σ = 109088510160. Its totient is φ = 54464854752.

The previous prime is 81756832319. The next prime is 81756832397. The reversal of 81756832371 is 17323865718.

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

It is not a de Polignac number, because 81756832371 - 2⁶ = 81756832307 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81756832571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9920236 + ... + 9928473.

It is an arithmetic number, because the mean of its divisors is an integer number (13636063770).

Almost surely, 2^81756832371 is an apocalyptic number.

81756832371 is a deficient number, since it is larger than the sum of its proper divisors (27331677789).

81756832371 is a wasteful number, since it uses less digits than its factorization.

81756832371 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19850085.

The product of its digits is 1693440, while the sum is 51.

The spelling of 81756832371 in words is "eighty-one billion, seven hundred fifty-six million, eight hundred thirty-two thousand, three hundred seventy-one".