213123191 has 2 divisors, whose sum is σ = 213123192. Its totient is φ = 213123190.

The previous prime is 213123187. The next prime is 213123199. The reversal of 213123191 is 191321312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 213123191 - 2² = 213123187 is a prime.

It is a super-3 number, since 3×213123191³ (a number of 26 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213123199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106561595 + 106561596.

It is an arithmetic number, because the mean of its divisors is an integer number (106561596).

Almost surely, 2^213123191 is an apocalyptic number.

213123191 is a deficient number, since it is larger than the sum of its proper divisors (1).

213123191 is an equidigital number, since it uses as much as digits as its factorization.

213123191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 324, while the sum is 23.

The square root of 213123191 is about 14598.7393633834. The cubic root of 213123191 is about 597.3243740753.

The spelling of 213123191 in words is "two hundred thirteen million, one hundred twenty-three thousand, one hundred ninety-one".