30909091 has 4 divisors (see below), whose sum is σ = 30952800. Its totient is φ = 30865384.

The previous prime is 30909089. The next prime is 30909113. The reversal of 30909091 is 19090903.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 30909091 - 2¹ = 30909089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30909031) 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, 20776 + ... + 22213.

It is an arithmetic number, because the mean of its divisors is an integer number (7738200).

Almost surely, 2^30909091 is an apocalyptic number.

30909091 is a deficient number, since it is larger than the sum of its proper divisors (43709).

30909091 is an equidigital number, since it uses as much as digits as its factorization.

30909091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43708.

The product of its (nonzero) digits is 2187, while the sum is 31.

The square root of 30909091 is about 5559.5944996016. The cubic root of 30909091 is about 313.8306895528.

Adding to 30909091 its reverse (19090903), we get a palindrome (49999994).

The spelling of 30909091 in words is "thirty million, nine hundred nine thousand, ninety-one".