667873657 has 6 divisors (see below), whose sum is σ = 734109194. Its totient is φ = 607157760.

The previous prime is 667873649. The next prime is 667873667. The reversal of 667873657 is 756378766.

It can be written as a sum of positive squares in only one way, i.e., 664814656 + 3059001 = 25784^2 + 1749^2 .

It is not a de Polignac number, because 667873657 - 2³ = 667873649 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 667873598 and 667873607.

It is not an unprimeable number, because it can be changed into a prime (667873607) 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 in 5 ways as a sum of consecutive naturals, for example, 2759688 + ... + 2759929.

Almost surely, 2^667873657 is an apocalyptic number.

It is an amenable number.

667873657 is a deficient number, since it is larger than the sum of its proper divisors (66235537).

667873657 is a wasteful number, since it uses less digits than its factorization.

667873657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5519639 (or 5519628 counting only the distinct ones).

The product of its digits is 8890560, while the sum is 55.

The square root of 667873657 is about 25843.2516723419. The cubic root of 667873657 is about 874.1073484805.

The spelling of 667873657 in words is "six hundred sixty-seven million, eight hundred seventy-three thousand, six hundred fifty-seven".