687642563 has 2 divisors, whose sum is σ = 687642564. Its totient is φ = 687642562.

The previous prime is 687642551. The next prime is 687642583. The reversal of 687642563 is 365246786.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 687642563 - 2¹⁶ = 687577027 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (687642583) 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 as a sum of consecutive naturals, namely, 343821281 + 343821282.

It is an arithmetic number, because the mean of its divisors is an integer number (343821282).

Almost surely, 2^687642563 is an apocalyptic number.

687642563 is a deficient number, since it is larger than the sum of its proper divisors (1).

687642563 is an equidigital number, since it uses as much as digits as its factorization.

687642563 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1451520, while the sum is 47.

The square root of 687642563 is about 26222.9396330770. The cubic root of 687642563 is about 882.6480853182.

The spelling of 687642563 in words is "six hundred eighty-seven million, six hundred forty-two thousand, five hundred sixty-three".