667728727 has 2 divisors, whose sum is σ = 667728728. Its totient is φ = 667728726.

The previous prime is 667728667. The next prime is 667728731. The reversal of 667728727 is 727827766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 667728727 - 2⁷ = 667728599 is a prime.

It is a super-2 number, since 2×667728727² = 891723305722081058, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667728757) 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, 333864363 + 333864364.

It is an arithmetic number, because the mean of its divisors is an integer number (333864364).

Almost surely, 2^667728727 is an apocalyptic number.

667728727 is a deficient number, since it is larger than the sum of its proper divisors (1).

667728727 is an equidigital number, since it uses as much as digits as its factorization.

667728727 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2765952, while the sum is 52.

The square root of 667728727 is about 25840.4474999950. The cubic root of 667728727 is about 874.0441161903.

The spelling of 667728727 in words is "six hundred sixty-seven million, seven hundred twenty-eight thousand, seven hundred twenty-seven".