667181663 has 2 divisors, whose sum is σ = 667181664. Its totient is φ = 667181662.

The previous prime is 667181651. The next prime is 667181681. The reversal of 667181663 is 366181766.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 667181663 - 2⁸ = 667181407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667181693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333590831 + 333590832.

It is an arithmetic number, because the mean of its divisors is an integer number (333590832).

Almost surely, 2^667181663 is an apocalyptic number.

667181663 is a deficient number, since it is larger than the sum of its proper divisors (1).

667181663 is an equidigital number, since it uses as much as digits as its factorization.

667181663 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 44.

The square root of 667181663 is about 25829.8599105764. The cubic root of 667181663 is about 873.8053522062.

The spelling of 667181663 in words is "six hundred sixty-seven million, one hundred eighty-one thousand, six hundred sixty-three".