665474879 has 2 divisors, whose sum is σ = 665474880. Its totient is φ = 665474878.

The previous prime is 665474869. The next prime is 665474881. The reversal of 665474879 is 978474566.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665474879 is a prime.

Together with 665474881, 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 (665474819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332737439 + 332737440.

It is an arithmetic number, because the mean of its divisors is an integer number (332737440).

Almost surely, 2^665474879 is an apocalyptic number.

665474879 is a deficient number, since it is larger than the sum of its proper divisors (1).

665474879 is an equidigital number, since it uses as much as digits as its factorization.

665474879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10160640, while the sum is 56.

The square root of 665474879 is about 25796.7997821435. The cubic root of 665474879 is about 873.0595930168.

The spelling of 665474879 in words is "six hundred sixty-five million, four hundred seventy-four thousand, eight hundred seventy-nine".