81157338361 has 8 divisors (see below), whose sum is σ = 91588219200. Its totient is φ = 71235281040.

The previous prime is 81157338341. The next prime is 81157338389. The reversal of 81157338361 is 16383375118.

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

It is not a de Polignac number, because 81157338361 - 2²⁵ = 81123783929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81157338341) 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, 127205541 + ... + 127206178.

It is an arithmetic number, because the mean of its divisors is an integer number (11448527400).

Almost surely, 2^81157338361 is an apocalyptic number.

It is an amenable number.

81157338361 is a deficient number, since it is larger than the sum of its proper divisors (10430880839).

81157338361 is a wasteful number, since it uses less digits than its factorization.

81157338361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254411759.

The product of its digits is 362880, while the sum is 46.

The spelling of 81157338361 in words is "eighty-one billion, one hundred fifty-seven million, three hundred thirty-eight thousand, three hundred sixty-one".