2123021191 has 2 divisors, whose sum is σ = 2123021192. Its totient is φ = 2123021190.

The previous prime is 2123021189. The next prime is 2123021203. The reversal of 2123021191 is 1911203212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2123021191 - 2¹ = 2123021189 is a prime.

Together with 2123021189, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2123021171) 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, 1061510595 + 1061510596.

It is an arithmetic number, because the mean of its divisors is an integer number (1061510596).

Almost surely, 2^2123021191 is an apocalyptic number.

2123021191 is a deficient number, since it is larger than the sum of its proper divisors (1).

2123021191 is an equidigital number, since it uses as much as digits as its factorization.

2123021191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 2123021191 is about 46076.2540903663. The cubic root of 2123021191 is about 1285.2416066769.

It can be divided in two parts, 2123021 and 191, that added together give a palindrome (2123212).

The spelling of 2123021191 in words is "two billion, one hundred twenty-three million, twenty-one thousand, one hundred ninety-one".