30508021 has 2 divisors, whose sum is σ = 30508022. Its totient is φ = 30508020.

The previous prime is 30508003. The next prime is 30508033. The reversal of 30508021 is 12080503.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30371121 + 136900 = 5511^2 + 370^2 .

It is an emirp because it is prime and its reverse (12080503) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 30508021 - 2¹³ = 30499829 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30508021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30508921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15254010 + 15254011.

It is an arithmetic number, because the mean of its divisors is an integer number (15254011).

Almost surely, 2^30508021 is an apocalyptic number.

It is an amenable number.

30508021 is a deficient number, since it is larger than the sum of its proper divisors (1).

30508021 is an equidigital number, since it uses as much as digits as its factorization.

30508021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 30508021 is about 5523.4066480751. The cubic root of 30508021 is about 312.4673749407.

Adding to 30508021 its reverse (12080503), we get a palindrome (42588524).

The spelling of 30508021 in words is "thirty million, five hundred eight thousand, twenty-one".