666658543 has 2 divisors, whose sum is σ = 666658544. Its totient is φ = 666658542.

The previous prime is 666658469. The next prime is 666658549. The reversal of 666658543 is 345856666.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666658543 is a prime.

It is a super-2 number, since 2×666658543² = 888867225909765698, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666658549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333329271 + 333329272.

It is an arithmetic number, because the mean of its divisors is an integer number (333329272).

Almost surely, 2^666658543 is an apocalyptic number.

666658543 is a deficient number, since it is larger than the sum of its proper divisors (1).

666658543 is an equidigital number, since it uses as much as digits as its factorization.

666658543 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3110400, while the sum is 49.

The square root of 666658543 is about 25819.7316601083. The cubic root of 666658543 is about 873.5769163836.

The spelling of 666658543 in words is "six hundred sixty-six million, six hundred fifty-eight thousand, five hundred forty-three".