81386290173 has 8 divisors (see below), whose sum is σ = 110354292000. Its totient is φ = 53337907568.

The previous prime is 81386290159. The next prime is 81386290177. The reversal of 81386290173 is 37109268318.

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

It is a cyclic number.

It is not a de Polignac number, because 81386290173 - 2⁴ = 81386290157 is a prime.

It is a super-3 number, since 3×81386290173³ (a number of 34 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81386290177) 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, 229904598 + ... + 229904951.

It is an arithmetic number, because the mean of its divisors is an integer number (13794286500).

Almost surely, 2^81386290173 is an apocalyptic number.

It is an amenable number.

81386290173 is a deficient number, since it is larger than the sum of its proper divisors (28968001827).

81386290173 is a wasteful number, since it uses less digits than its factorization.

81386290173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459809611.

The product of its (nonzero) digits is 435456, while the sum is 48.

The spelling of 81386290173 in words is "eighty-one billion, three hundred eighty-six million, two hundred ninety thousand, one hundred seventy-three".