343816021 has 2 divisors, whose sum is σ = 343816022. Its totient is φ = 343816020.

The previous prime is 343815961. The next prime is 343816049. The reversal of 343816021 is 120618343.

It is an a-pointer prime, because the next prime (343816049) can be obtained adding 343816021 to its sum of digits (28).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 280931121 + 62884900 = 16761^2 + 7930^2 .

It is an emirp because it is prime and its reverse (120618343) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 343816021 - 2¹⁹ = 343291733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (343816091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171908010 + 171908011.

It is an arithmetic number, because the mean of its divisors is an integer number (171908011).

Almost surely, 2^343816021 is an apocalyptic number.

It is an amenable number.

343816021 is a deficient number, since it is larger than the sum of its proper divisors (1).

343816021 is an equidigital number, since it uses as much as digits as its factorization.

343816021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 343816021 is about 18542.2765862232. The cubic root of 343816021 is about 700.5546766873.

The spelling of 343816021 in words is "three hundred forty-three million, eight hundred sixteen thousand, twenty-one".