30819421 has 2 divisors, whose sum is σ = 30819422. Its totient is φ = 30819420.

The previous prime is 30819361. The next prime is 30819449. The reversal of 30819421 is 12491803.

It is a happy number.

It is an a-pointer prime, because the next prime (30819449) can be obtained adding 30819421 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., 16112196 + 14707225 = 4014^2 + 3835^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30819421 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30819421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30819461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15409710 + 15409711.

It is an arithmetic number, because the mean of its divisors is an integer number (15409711).

Almost surely, 2^30819421 is an apocalyptic number.

It is an amenable number.

30819421 is a deficient number, since it is larger than the sum of its proper divisors (1).

30819421 is an equidigital number, since it uses as much as digits as its factorization.

30819421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 30819421 is about 5551.5242051170. The cubic root of 30819421 is about 313.5269120952.

The spelling of 30819421 in words is "thirty million, eight hundred nineteen thousand, four hundred twenty-one".