30120809 has 4 divisors (see below), whose sum is σ = 31092480. Its totient is φ = 29149140.

The previous prime is 30120803. The next prime is 30120817. The reversal of 30120809 is 90802103.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30120809 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (30120803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 485789 + ... + 485850.

It is an arithmetic number, because the mean of its divisors is an integer number (7773120).

Almost surely, 2^30120809 is an apocalyptic number.

It is an amenable number.

30120809 is a deficient number, since it is larger than the sum of its proper divisors (971671).

30120809 is an equidigital number, since it uses as much as digits as its factorization.

30120809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971670.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 30120809 is about 5488.2427971073. The cubic root of 30120809 is about 311.1397826987.

The spelling of 30120809 in words is "thirty million, one hundred twenty thousand, eight hundred nine".