30393821 has 2 divisors, whose sum is σ = 30393822. Its totient is φ = 30393820.

The previous prime is 30393817. The next prime is 30393871. The reversal of 30393821 is 12839303.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29268100 + 1125721 = 5410^2 + 1061^2 .

It is a cyclic number.

It is not a de Polignac number, because 30393821 - 2² = 30393817 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30393871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15196910 + 15196911.

It is an arithmetic number, because the mean of its divisors is an integer number (15196911).

Almost surely, 2^30393821 is an apocalyptic number.

It is an amenable number.

30393821 is a deficient number, since it is larger than the sum of its proper divisors (1).

30393821 is an equidigital number, since it uses as much as digits as its factorization.

30393821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 30393821 is about 5513.0591326413. The cubic root of 30393821 is about 312.0770033747.

The spelling of 30393821 in words is "thirty million, three hundred ninety-three thousand, eight hundred twenty-one".