671623663 has 2 divisors, whose sum is σ = 671623664. Its totient is φ = 671623662.

The previous prime is 671623657. The next prime is 671623721. The reversal of 671623663 is 366326176.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 671623663 - 2¹³ = 671615471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671623613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335811831 + 335811832.

It is an arithmetic number, because the mean of its divisors is an integer number (335811832).

Almost surely, 2^671623663 is an apocalyptic number.

671623663 is a deficient number, since it is larger than the sum of its proper divisors (1).

671623663 is an equidigital number, since it uses as much as digits as its factorization.

671623663 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 40.

The square root of 671623663 is about 25915.7030195980. The cubic root of 671623663 is about 875.7402880110.

The spelling of 671623663 in words is "six hundred seventy-one million, six hundred twenty-three thousand, six hundred sixty-three".