665776043 has 2 divisors, whose sum is σ = 665776044. Its totient is φ = 665776042.

The previous prime is 665776031. The next prime is 665776073. The reversal of 665776043 is 340677566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665776043 - 2⁸ = 665775787 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 665775985 and 665776003.

It is not a weakly prime, because it can be changed into another prime (665776073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332888021 + 332888022.

It is an arithmetic number, because the mean of its divisors is an integer number (332888022).

Almost surely, 2^665776043 is an apocalyptic number.

665776043 is a deficient number, since it is larger than the sum of its proper divisors (1).

665776043 is an equidigital number, since it uses as much as digits as its factorization.

665776043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 635040, while the sum is 44.

The square root of 665776043 is about 25802.6363575508. The cubic root of 665776043 is about 873.1912756560.

The spelling of 665776043 in words is "six hundred sixty-five million, seven hundred seventy-six thousand, forty-three".