213406181 has 2 divisors, whose sum is σ = 213406182. Its totient is φ = 213406180.

The previous prime is 213406169. The next prime is 213406187. The reversal of 213406181 is 181604312.

213406181 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129390625 + 84015556 = 11375^2 + 9166^2 .

It is a cyclic number.

It is not a de Polignac number, because 213406181 - 2²⁶ = 146297317 is a prime.

It is a super-2 number, since 2×213406181² = 91084396178009522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 213406181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213406187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106703090 + 106703091.

It is an arithmetic number, because the mean of its divisors is an integer number (106703091).

Almost surely, 2^213406181 is an apocalyptic number.

It is an amenable number.

213406181 is a deficient number, since it is larger than the sum of its proper divisors (1).

213406181 is an equidigital number, since it uses as much as digits as its factorization.

213406181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 213406181 is about 14608.4284233452. The cubic root of 213406181 is about 597.5886376091.

The spelling of 213406181 in words is "two hundred thirteen million, four hundred six thousand, one hundred eighty-one".