2121111010091 has 2 divisors, whose sum is σ = 2121111010092. Its totient is φ = 2121111010090.

The previous prime is 2121111010061. The next prime is 2121111010093. The reversal of 2121111010091 is 1900101111212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2121111010091 - 2¹⁰ = 2121111009067 is a prime.

It is a super-2 number, since 2×2121111010091² (a number of 25 digits) contains 22 as substring.

Together with 2121111010093, 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 (2121111010093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060555505045 + 1060555505046.

It is an arithmetic number, because the mean of its divisors is an integer number (1060555505046).

Almost surely, 2^{2121111010091} is an apocalyptic number.

2121111010091 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121111010091 is an equidigital number, since it uses as much as digits as its factorization.

2121111010091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 20.

The spelling of 2121111010091 in words is "two trillion, one hundred twenty-one billion, one hundred eleven million, ten thousand, ninety-one".