81910793183 has 4 divisors (see below), whose sum is σ = 82460530200. Its totient is φ = 81361056168.

The previous prime is 81910793149. The next prime is 81910793197. The reversal of 81910793183 is 38139701918.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81910793183 - 2²⁴ = 81894015967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81910793383) 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, 274868285 + ... + 274868582.

It is an arithmetic number, because the mean of its divisors is an integer number (20615132550).

Almost surely, 2^81910793183 is an apocalyptic number.

81910793183 is a deficient number, since it is larger than the sum of its proper divisors (549737017).

81910793183 is a wasteful number, since it uses less digits than its factorization.

81910793183 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 549737016.

The product of its (nonzero) digits is 326592, while the sum is 50.

The spelling of 81910793183 in words is "eighty-one billion, nine hundred ten million, seven hundred ninety-three thousand, one hundred eighty-three".