81086241205 has 8 divisors (see below), whose sum is σ = 97319794104. Its totient is φ = 64858123200.

The previous prime is 81086241199. The next prime is 81086241209. The reversal of 81086241205 is 50214268018.

It can be written as a sum of positive squares in 4 ways, for example, as 2555706916 + 78530534289 = 50554^2 + 280233^2 .

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

It is not a de Polignac number, because 81086241205 - 2¹³ = 81086233013 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 (81086241209) 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, 1325826 + ... + 1385635.

It is an arithmetic number, because the mean of its divisors is an integer number (12164974263).

Almost surely, 2^81086241205 is an apocalyptic number.

It is an amenable number.

81086241205 is a deficient number, since it is larger than the sum of its proper divisors (16233552899).

81086241205 is a wasteful number, since it uses less digits than its factorization.

81086241205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2717447.

The product of its (nonzero) digits is 30720, while the sum is 37.

The spelling of 81086241205 in words is "eighty-one billion, eighty-six million, two hundred forty-one thousand, two hundred five".