666698443 has 2 divisors, whose sum is σ = 666698444. Its totient is φ = 666698442.

The previous prime is 666698399. The next prime is 666698453. The reversal of 666698443 is 344896666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666698443 - 2¹⁷ = 666567371 is a prime.

It is not a weakly prime, because it can be changed into another prime (666698453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333349221 + 333349222.

It is an arithmetic number, because the mean of its divisors is an integer number (333349222).

Almost surely, 2^666698443 is an apocalyptic number.

666698443 is a deficient number, since it is larger than the sum of its proper divisors (1).

666698443 is an equidigital number, since it uses as much as digits as its factorization.

666698443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4478976, while the sum is 52.

The square root of 666698443 is about 25820.5043134328. The cubic root of 666698443 is about 873.5943441078.

The spelling of 666698443 in words is "six hundred sixty-six million, six hundred ninety-eight thousand, four hundred forty-three".