306116021 has 2 divisors, whose sum is σ = 306116022. Its totient is φ = 306116020.

The previous prime is 306116009. The next prime is 306116023. The reversal of 306116021 is 120611603.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 283922500 + 22193521 = 16850^2 + 4711^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-306116021 is a prime.

Together with 306116023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 306115984 and 306116002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (306116023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 153058010 + 153058011.

It is an arithmetic number, because the mean of its divisors is an integer number (153058011).

Almost surely, 2^306116021 is an apocalyptic number.

It is an amenable number.

306116021 is a deficient number, since it is larger than the sum of its proper divisors (1).

306116021 is an equidigital number, since it uses as much as digits as its factorization.

306116021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 306116021 is about 17496.1716098122. The cubic root of 306116021 is about 673.9515656097.

Adding to 306116021 its reverse (120611603), we get a palindrome (426727624).

It can be divided in two parts, 30611602 and 1, that added together give a palindrome (30611603).

The spelling of 306116021 in words is "three hundred six million, one hundred sixteen thousand, twenty-one".