1001111081 has 2 divisors, whose sum is σ = 1001111082. Its totient is φ = 1001111080.

The previous prime is 1001111053. The next prime is 1001111093. The reversal of 1001111081 is 1801111001.

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., 895206400 + 105904681 = 29920^2 + 10291^2 .

It is an emirp because it is prime and its reverse (1801111001) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001111081 is a prime.

It is a super-3 number, since 3×1001111081³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (1001111381) 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, 500555540 + 500555541.

It is an arithmetic number, because the mean of its divisors is an integer number (500555541).

Almost surely, 2^1001111081 is an apocalyptic number.

It is an amenable number.

1001111081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001111081 is an equidigital number, since it uses as much as digits as its factorization.

1001111081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 14.

The square root of 1001111081 is about 31640.3394577239. The cubic root of 1001111081 is about 1000.3702232512.

Adding to 1001111081 its reverse (1801111001), we get a palindrome (2802222082).

The spelling of 1001111081 in words is "one billion, one million, one hundred eleven thousand, eighty-one".