81858605195 has 16 divisors (see below), whose sum is σ = 101092467648. Its totient is φ = 63586062720.

The previous prime is 81858605183. The next prime is 81858605221. The reversal of 81858605195 is 59150685818.

It is a happy number.

It is not a de Polignac number, because 81858605195 - 2⁸ = 81858604939 is a prime.

It is a super-4 number, since 4×81858605195⁴ (a number of 45 digits) contains 4444 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81858605195.

It is an unprimeable number.

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, 364196 + ... + 544385.

It is an arithmetic number, because the mean of its divisors is an integer number (6318279228).

Almost surely, 2^81858605195 is an apocalyptic number.

81858605195 is a deficient number, since it is larger than the sum of its proper divisors (19233862453).

81858605195 is a wasteful number, since it uses less digits than its factorization.

81858605195 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 909110.

The product of its (nonzero) digits is 3456000, while the sum is 56.

The spelling of 81858605195 in words is "eighty-one billion, eight hundred fifty-eight million, six hundred five thousand, one hundred ninety-five".