661345343 has 2 divisors, whose sum is σ = 661345344. Its totient is φ = 661345342.

The previous prime is 661345303. The next prime is 661345361. The reversal of 661345343 is 343543166.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 661345343 - 2¹⁶ = 661279807 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661345303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330672671 + 330672672.

It is an arithmetic number, because the mean of its divisors is an integer number (330672672).

Almost surely, 2^661345343 is an apocalyptic number.

661345343 is a deficient number, since it is larger than the sum of its proper divisors (1).

661345343 is an equidigital number, since it uses as much as digits as its factorization.

661345343 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 35.

The square root of 661345343 is about 25716.6355303333. The cubic root of 661345343 is about 871.2499507831.

The spelling of 661345343 in words is "six hundred sixty-one million, three hundred forty-five thousand, three hundred forty-three".