12111211011001 has 2 divisors, whose sum is σ = 12111211011002. Its totient is φ = 12111211011000.

The previous prime is 12111211010999. The next prime is 12111211011043. The reversal of 12111211011001 is 10011011211121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12059089664400 + 52121346601 = 3472620^2 + 228301^2 .

It is a cyclic number.

It is not a de Polignac number, because 12111211011001 - 2¹ = 12111211010999 is a prime.

Together with 12111211010999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (12111211011061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6055605505500 + 6055605505501.

It is an arithmetic number, because the mean of its divisors is an integer number (6055605505501).

Almost surely, 2^{12111211011001} is an apocalyptic number.

It is an amenable number.

12111211011001 is a deficient number, since it is larger than the sum of its proper divisors (1).

12111211011001 is an equidigital number, since it uses as much as digits as its factorization.

12111211011001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 12111211011001 its reverse (10011011211121), we get a palindrome (22122222222122).

The spelling of 12111211011001 in words is "twelve trillion, one hundred eleven billion, two hundred eleven million, eleven thousand, one".