91523752981 has 2 divisors, whose sum is σ = 91523752982. Its totient is φ = 91523752980.

The previous prime is 91523752979. The next prime is 91523753011. The reversal of 91523752981 is 18925732519.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78181192881 + 13342560100 = 279609^2 + 115510^2 .

It is a cyclic number.

It is not a de Polignac number, because 91523752981 - 2¹ = 91523752979 is a prime.

It is a super-2 number, since 2×91523752981² (a number of 23 digits) contains 22 as substring.

Together with 91523752979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91523752181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45761876490 + 45761876491.

It is an arithmetic number, because the mean of its divisors is an integer number (45761876491).

Almost surely, 2^91523752981 is an apocalyptic number.

It is an amenable number.

91523752981 is a deficient number, since it is larger than the sum of its proper divisors (1).

91523752981 is an equidigital number, since it uses as much as digits as its factorization.

91523752981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1360800, while the sum is 52.

The spelling of 91523752981 in words is "ninety-one billion, five hundred twenty-three million, seven hundred fifty-two thousand, nine hundred eighty-one".