81011475101 has 2 divisors, whose sum is σ = 81011475102. Its totient is φ = 81011475100.

The previous prime is 81011475073. The next prime is 81011475107. The reversal of 81011475101 is 10157411018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74994370201 + 6017104900 = 273851^2 + 77570^2 .

It is a cyclic number.

It is not a de Polignac number, because 81011475101 - 2³⁰ = 79937733277 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81011475107) by changing a digit.

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 as a sum of consecutive naturals, namely, 40505737550 + 40505737551.

It is an arithmetic number, because the mean of its divisors is an integer number (40505737551).

Almost surely, 2^81011475101 is an apocalyptic number.

It is an amenable number.

81011475101 is a deficient number, since it is larger than the sum of its proper divisors (1).

81011475101 is an equidigital number, since it uses as much as digits as its factorization.

81011475101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1120, while the sum is 29.

Adding to 81011475101 its reverse (10157411018), we get a palindrome (91168886119).

The spelling of 81011475101 in words is "eighty-one billion, eleven million, four hundred seventy-five thousand, one hundred one".