11011111121 has 2 divisors, whose sum is σ = 11011111122.
Its totient is φ = 11011111120.
The previous prime is 11011111117. The next prime is 11011111129. The reversal of 11011111121 is 12111111011.
Adding to 11011111121 its reverse (12111111011), we get a palindrome (23122222132).
It is a happy number.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 8734771600 + 2276339521 = 93460^2 + 47711^2
It is a cyclic number.
It is not a de Polignac number, because 11011111121 - 22 = 11011111117 is a prime.
It is not a weakly prime, because it can be changed into another prime (11011111129) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5505555560 + 5505555561.
It is an arithmetic number, because the mean of its divisors is an integer number (5505555561).
Almost surely, 211011111121 is an apocalyptic number.
It is an amenable number.
11011111121 is a deficient number, since it is larger than the sum of its proper divisors (1).
11011111121 is an equidigital number, since it uses as much as digits as its factorization.
11011111121 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 2, while the sum is 11.
The spelling of 11011111121 in words is "eleven billion, eleven million, one hundred eleven thousand, one hundred twenty-one".