91785692364281 has 2 divisors, whose sum is σ = 91785692364282. Its totient is φ = 91785692364280.

The previous prime is 91785692364269. The next prime is 91785692364287. The reversal of 91785692364281 is 18246329658719.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78289032875881 + 13496659488400 = 8848109^2 + 3673780^2 .

It is a cyclic number.

It is not a de Polignac number, because 91785692364281 - 2¹⁰ = 91785692363257 is a prime.

It is a super-2 number, since 2×91785692364281² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91785692364287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45892846182140 + 45892846182141.

It is an arithmetic number, because the mean of its divisors is an integer number (45892846182141).

Almost surely, 2^{91785692364281} is an apocalyptic number.

It is an amenable number.

91785692364281 is a deficient number, since it is larger than the sum of its proper divisors (1).

91785692364281 is an equidigital number, since it uses as much as digits as its factorization.

91785692364281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 313528320, while the sum is 71.

The spelling of 91785692364281 in words is "ninety-one trillion, seven hundred eighty-five billion, six hundred ninety-two million, three hundred sixty-four thousand, two hundred eighty-one".