343540781 has 2 divisors, whose sum is σ = 343540782. Its totient is φ = 343540780.

The previous prime is 343540739. The next prime is 343540783. The reversal of 343540781 is 187045343.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217090756 + 126450025 = 14734^2 + 11245^2 .

It is a cyclic number.

It is not a de Polignac number, because 343540781 - 2¹⁴ = 343524397 is a prime.

It is a super-2 number, since 2×343540781² = 236040536420179922, which contains 22 as substring.

Together with 343540783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (343540783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171770390 + 171770391.

It is an arithmetic number, because the mean of its divisors is an integer number (171770391).

Almost surely, 2^343540781 is an apocalyptic number.

It is an amenable number.

343540781 is a deficient number, since it is larger than the sum of its proper divisors (1).

343540781 is an equidigital number, since it uses as much as digits as its factorization.

343540781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 343540781 is about 18534.8531421212. The cubic root of 343540781 is about 700.3676850656.

The spelling of 343540781 in words is "three hundred forty-three million, five hundred forty thousand, seven hundred eighty-one".