11928368581 has 2 divisors, whose sum is σ = 11928368582. Its totient is φ = 11928368580.

The previous prime is 11928368519. The next prime is 11928368623. The reversal of 11928368581 is 18586382911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10554480225 + 1373888356 = 102735^2 + 37066^2 .

It is a cyclic number.

It is not a de Polignac number, because 11928368581 - 2⁹ = 11928368069 is a prime.

It is a super-2 number, since 2×11928368581² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11928368381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5964184290 + 5964184291.

It is an arithmetic number, because the mean of its divisors is an integer number (5964184291).

Almost surely, 2^11928368581 is an apocalyptic number.

It is an amenable number.

11928368581 is a deficient number, since it is larger than the sum of its proper divisors (1).

11928368581 is an equidigital number, since it uses as much as digits as its factorization.

11928368581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 829440, while the sum is 52.

The spelling of 11928368581 in words is "eleven billion, nine hundred twenty-eight million, three hundred sixty-eight thousand, five hundred eighty-one".