111101011111001 has 2 divisors, whose sum is σ = 111101011111002. Its totient is φ = 111101011111000.

The previous prime is 111101011110989. The next prime is 111101011111003. The reversal of 111101011111001 is 100111110101111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61721214001225 + 49379797109776 = 7856285^2 + 7027076^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111101011111001 is a prime.

Together with 111101011111003, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (111101011111003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55550505555500 + 55550505555501.

It is an arithmetic number, because the mean of its divisors is an integer number (55550505555501).

Almost surely, 2^{111101011111001} is an apocalyptic number.

It is an amenable number.

111101011111001 is a deficient number, since it is larger than the sum of its proper divisors (1).

111101011111001 is an equidigital number, since it uses as much as digits as its factorization.

111101011111001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1, while the sum is 11.

Adding to 111101011111001 its reverse (100111110101111), we get a palindrome (211212121212112).

It can be divided in two parts, 11110101111 and 1001, that multiplied together give a palindrome (11121211212111).

The spelling of 111101011111001 in words is "one hundred eleven trillion, one hundred one billion, eleven million, one hundred eleven thousand, one".