30309681 has 4 divisors (see below), whose sum is σ = 40412912. Its totient is φ = 20206452.

The previous prime is 30309679. The next prime is 30309703. The reversal of 30309681 is 18690303.

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 not a de Polignac number, because 30309681 - 2¹ = 30309679 is a prime.

It is a super-2 number, since 2×30309681² = 1837353524643522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30309781) 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, 5051611 + ... + 5051616.

It is an arithmetic number, because the mean of its divisors is an integer number (10103228).

Almost surely, 2^30309681 is an apocalyptic number.

It is an amenable number.

30309681 is a deficient number, since it is larger than the sum of its proper divisors (10103231).

30309681 is a wasteful number, since it uses less digits than its factorization.

30309681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10103230.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 30309681 is about 5505.4228720417. The cubic root of 30309681 is about 311.7887602832.

Adding to 30309681 its reverse (18690303), we get a palindrome (48999984).

The spelling of 30309681 in words is "thirty million, three hundred nine thousand, six hundred eighty-one".