81793432158 has 32 divisors (see below), whose sum is σ = 172213612800. Its totient is φ = 25826967936.

The previous prime is 81793432153. The next prime is 81793432159. The reversal of 81793432158 is 85123439718.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 81793432158.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81793432151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1378038 + ... + 1436166.

It is an arithmetic number, because the mean of its divisors is an integer number (5381675400).

Almost surely, 2^81793432158 is an apocalyptic number.

81793432158 is an abundant number, since it is smaller than the sum of its proper divisors (90420180642).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81793432158 is a wasteful number, since it uses less digits than its factorization.

81793432158 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70496.

The product of its digits is 1451520, while the sum is 51.

The spelling of 81793432158 in words is "eighty-one billion, seven hundred ninety-three million, four hundred thirty-two thousand, one hundred fifty-eight".