81358308361 has 16 divisors (see below), whose sum is σ = 93371227200. Its totient is φ = 70201297600.

The previous prime is 81358308341. The next prime is 81358308371. The reversal of 81358308361 is 16380385318.

It is not a de Polignac number, because 81358308361 - 2¹³ = 81358300169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81358308341) 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, 2142550 + ... + 2180191.

It is an arithmetic number, because the mean of its divisors is an integer number (5835701700).

Almost surely, 2^81358308361 is an apocalyptic number.

It is an amenable number.

81358308361 is a deficient number, since it is larger than the sum of its proper divisors (12012918839).

81358308361 is a wasteful number, since it uses less digits than its factorization.

81358308361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4322840.

The product of its (nonzero) digits is 414720, while the sum is 46.

The spelling of 81358308361 in words is "eighty-one billion, three hundred fifty-eight million, three hundred eight thousand, three hundred sixty-one".