81793891355 has 16 divisors (see below), whose sum is σ = 107103299328. Its totient is φ = 59471100000.

The previous prime is 81793891349. The next prime is 81793891391. The reversal of 81793891355 is 55319839718.

It is a happy number.

It is not a de Polignac number, because 81793891355 - 2²² = 81789697051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81793891294 and 81793891303.

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 15 ways as a sum of consecutive naturals, for example, 24980 + ... + 405230.

It is an arithmetic number, because the mean of its divisors is an integer number (6693956208).

Almost surely, 2^81793891355 is an apocalyptic number.

81793891355 is a deficient number, since it is larger than the sum of its proper divisors (25309407973).

81793891355 is a wasteful number, since it uses less digits than its factorization.

81793891355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384178.

The product of its digits is 8164800, while the sum is 59.

The spelling of 81793891355 in words is "eighty-one billion, seven hundred ninety-three million, eight hundred ninety-one thousand, three hundred fifty-five".