30998909 has 2 divisors, whose sum is σ = 30998910. Its totient is φ = 30998908.

The previous prime is 30998881. The next prime is 30998987. The reversal of 30998909 is 90989903.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15960025 + 15038884 = 3995^2 + 3878^2 .

It is an emirp because it is prime and its reverse (90989903) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 30998909 - 2¹⁶ = 30933373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30998509) 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, 15499454 + 15499455.

It is an arithmetic number, because the mean of its divisors is an integer number (15499455).

Almost surely, 2^30998909 is an apocalyptic number.

It is an amenable number.

30998909 is a deficient number, since it is larger than the sum of its proper divisors (1).

30998909 is an equidigital number, since it uses as much as digits as its factorization.

30998909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 47.

The square root of 30998909 is about 5567.6663872757. Note that the first 3 decimals coincide. The cubic root of 30998909 is about 314.1343799848.

It can be divided in two parts, 30998 and 909, that multiplied together give a palindrome (28177182).

The spelling of 30998909 in words is "thirty million, nine hundred ninety-eight thousand, nine hundred nine".