343216561 has 8 divisors (see below), whose sum is σ = 350216424. Its totient is φ = 336261120.

The previous prime is 343216547. The next prime is 343216591. The reversal of 343216561 is 165612343.

It can be written as a sum of positive squares in 4 ways, for example, as 94965025 + 248251536 = 9745^2 + 15756^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 343216561 - 2⁵ = 343216529 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (343216501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4731 + ... + 26623.

It is an arithmetic number, because the mean of its divisors is an integer number (43777053).

Almost surely, 2^343216561 is an apocalyptic number.

It is an amenable number.

343216561 is a deficient number, since it is larger than the sum of its proper divisors (6999863).

343216561 is a wasteful number, since it uses less digits than its factorization.

343216561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22211.

The product of its digits is 12960, while the sum is 31.

The square root of 343216561 is about 18526.1048523428. The cubic root of 343216561 is about 700.1472894143.

The spelling of 343216561 in words is "three hundred forty-three million, two hundred sixteen thousand, five hundred sixty-one".