343212121 has 6 divisors (see below), whose sum is σ = 399246810. Its totient is φ = 294181776.

The previous prime is 343212109. The next prime is 343212127. The reversal of 343212121 is 121212343.

It is a happy number.

343212121 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in only one way, i.e., 322382025 + 20830096 = 17955^2 + 4564^2 .

It is not a de Polignac number, because 343212121 - 2⁷ = 343211993 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

343212121 is a modest number, since divided by 212121 gives 343 as remainder.

It is not an unprimeable number, because it can be changed into a prime (343212127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3502116 + ... + 3502213.

It is an arithmetic number, because the mean of its divisors is an integer number (66541135).

Almost surely, 2^343212121 is an apocalyptic number.

It is an amenable number.

343212121 is a deficient number, since it is larger than the sum of its proper divisors (56034689).

343212121 is an equidigital number, since it uses as much as digits as its factorization.

343212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7004343 (or 7004336 counting only the distinct ones).

The product of its digits is 288, while the sum is 19.

The square root of 343212121 is about 18525.9850210454. The cubic root of 343212121 is about 700.1442702638.

Adding to 343212121 its reverse (121212343), we get a palindrome (464424464).

The spelling of 343212121 in words is "three hundred forty-three million, two hundred twelve thousand, one hundred twenty-one".