30868021 has 2 divisors, whose sum is σ = 30868022. Its totient is φ = 30868020.

The previous prime is 30868009. The next prime is 30868043. The reversal of 30868021 is 12086803.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21288996 + 9579025 = 4614^2 + 3095^2 .

It is an emirp because it is prime and its reverse (12086803) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 30868021 - 2¹⁷ = 30736949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30868081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15434010 + 15434011.

It is an arithmetic number, because the mean of its divisors is an integer number (15434011).

Almost surely, 2^30868021 is an apocalyptic number.

It is an amenable number.

30868021 is a deficient number, since it is larger than the sum of its proper divisors (1).

30868021 is an equidigital number, since it uses as much as digits as its factorization.

30868021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 30868021 is about 5555.8996571212. The cubic root of 30868021 is about 313.6916286388.

It can be divided in two parts, 3086802 and 1, that added together give a palindrome (3086803).

The spelling of 30868021 in words is "thirty million, eight hundred sixty-eight thousand, twenty-one".