81859594269 has 16 divisors (see below), whose sum is σ = 110026825920. Its totient is φ = 54133073280.

The previous prime is 81859594261. The next prime is 81859594283. The reversal of 81859594269 is 96249595818.

It is a happy number.

It is not a de Polignac number, because 81859594269 - 2³ = 81859594261 is a prime.

It is a super-2 number, since 2×81859594269² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81859594261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 890347 + ... + 977975.

It is an arithmetic number, because the mean of its divisors is an integer number (6876676620).

Almost surely, 2^81859594269 is an apocalyptic number.

It is an amenable number.

81859594269 is a deficient number, since it is larger than the sum of its proper divisors (28167231651).

81859594269 is a wasteful number, since it uses less digits than its factorization.

81859594269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90140.

The product of its digits is 55987200, while the sum is 66.

The spelling of 81859594269 in words is "eighty-one billion, eight hundred fifty-nine million, five hundred ninety-four thousand, two hundred sixty-nine".