667575779 has 4 divisors (see below), whose sum is σ = 718927776. Its totient is φ = 616223784.

The previous prime is 667575767. The next prime is 667575803. The reversal of 667575779 is 977575766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 977575766 = 2 ⋅488787883.

It is a cyclic number.

It is not a de Polignac number, because 667575779 - 2²⁰ = 666527203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667575179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25675979 + ... + 25676004.

It is an arithmetic number, because the mean of its divisors is an integer number (179731944).

Almost surely, 2^667575779 is an apocalyptic number.

667575779 is a deficient number, since it is larger than the sum of its proper divisors (51351997).

667575779 is a wasteful number, since it uses less digits than its factorization.

667575779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51351996.

The product of its digits is 19448100, while the sum is 59.

The square root of 667575779 is about 25837.4878616324. The cubic root of 667575779 is about 873.9773757599.

The spelling of 667575779 in words is "six hundred sixty-seven million, five hundred seventy-five thousand, seven hundred seventy-nine".