213221203813 has 2 divisors, whose sum is σ = 213221203814. Its totient is φ = 213221203812.

The previous prime is 213221203763. The next prime is 213221203841. The reversal of 213221203813 is 318302122312.

It is an a-pointer prime, because the next prime (213221203841) can be obtained adding 213221203813 to its sum of digits (28).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206790286564 + 6430917249 = 454742^2 + 80193^2 .

It is a cyclic number.

It is not a de Polignac number, because 213221203813 - 2⁹ = 213221203301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213221803813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106610601906 + 106610601907.

It is an arithmetic number, because the mean of its divisors is an integer number (106610601907).

Almost surely, 2^213221203813 is an apocalyptic number.

It is an amenable number.

213221203813 is a deficient number, since it is larger than the sum of its proper divisors (1).

213221203813 is an equidigital number, since it uses as much as digits as its factorization.

213221203813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 28.

The spelling of 213221203813 in words is "two hundred thirteen billion, two hundred twenty-one million, two hundred three thousand, eight hundred thirteen".