305681213 has 2 divisors, whose sum is σ = 305681214. Its totient is φ = 305681212.

The previous prime is 305681179. The next prime is 305681219. The reversal of 305681213 is 312186503.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 288558169 + 17123044 = 16987^2 + 4138^2 .

It is a cyclic number.

It is not a de Polignac number, because 305681213 - 2⁸ = 305680957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (305681219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152840606 + 152840607.

It is an arithmetic number, because the mean of its divisors is an integer number (152840607).

Almost surely, 2^305681213 is an apocalyptic number.

It is an amenable number.

305681213 is a deficient number, since it is larger than the sum of its proper divisors (1).

305681213 is an equidigital number, since it uses as much as digits as its factorization.

305681213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 305681213 is about 17483.7413902174. The cubic root of 305681213 is about 673.6323202185.

The spelling of 305681213 in words is "three hundred five million, six hundred eighty-one thousand, two hundred thirteen".