213221243 has 2 divisors, whose sum is σ = 213221244. Its totient is φ = 213221242.

The previous prime is 213221209. The next prime is 213221251. The reversal of 213221243 is 342122312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213221243 is a prime.

It is not a weakly prime, because it can be changed into another prime (213221143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106610621 + 106610622.

It is an arithmetic number, because the mean of its divisors is an integer number (106610622).

Almost surely, 2^213221243 is an apocalyptic number.

213221243 is a deficient number, since it is larger than the sum of its proper divisors (1).

213221243 is an equidigital number, since it uses as much as digits as its factorization.

213221243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 20.

The square root of 213221243 is about 14602.0972123870. The cubic root of 213221243 is about 597.4159640920.

Adding to 213221243 its reverse (342122312), we get a palindrome (555343555).

The spelling of 213221243 in words is "two hundred thirteen million, two hundred twenty-one thousand, two hundred forty-three".