11905311582581 has 2 divisors, whose sum is σ = 11905311582582. Its totient is φ = 11905311582580.

The previous prime is 11905311582523. The next prime is 11905311582623. The reversal of 11905311582581 is 18528511350911.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7004994423025 + 4900317159556 = 2646695^2 + 2213666^2 .

It is a cyclic number.

It is not a de Polignac number, because 11905311582581 - 2⁶ = 11905311582517 is a prime.

It is a super-3 number, since 3×11905311582581³ (a number of 40 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11905311582511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5952655791290 + 5952655791291.

It is an arithmetic number, because the mean of its divisors is an integer number (5952655791291).

Almost surely, 2^{11905311582581} is an apocalyptic number.

It is an amenable number.

11905311582581 is a deficient number, since it is larger than the sum of its proper divisors (1).

11905311582581 is an equidigital number, since it uses as much as digits as its factorization.

11905311582581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432000, while the sum is 50.

The spelling of 11905311582581 in words is "eleven trillion, nine hundred five billion, three hundred eleven million, five hundred eighty-two thousand, five hundred eighty-one".