81157338341 has 2 divisors, whose sum is σ = 81157338342. Its totient is φ = 81157338340.

The previous prime is 81157338271. The next prime is 81157338389. The reversal of 81157338341 is 14383375118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76026481441 + 5130856900 = 275729^2 + 71630^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81157338341 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81157338292 and 81157338301.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81157338641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40578669170 + 40578669171.

It is an arithmetic number, because the mean of its divisors is an integer number (40578669171).

Almost surely, 2^81157338341 is an apocalyptic number.

It is an amenable number.

81157338341 is a deficient number, since it is larger than the sum of its proper divisors (1).

81157338341 is an equidigital number, since it uses as much as digits as its factorization.

81157338341 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 44.

The spelling of 81157338341 in words is "eighty-one billion, one hundred fifty-seven million, three hundred thirty-eight thousand, three hundred forty-one".