665550066563 has 2 divisors, whose sum is σ = 665550066564. Its totient is φ = 665550066562.

The previous prime is 665550066541. The next prime is 665550066593. The reversal of 665550066563 is 365660055566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665550066563 - 2³⁴ = 648370197379 is a prime.

It is a super-2 number, since 2×665550066563² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (665550066593) 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, 332775033281 + 332775033282.

It is an arithmetic number, because the mean of its divisors is an integer number (332775033282).

Almost surely, 2^665550066563 is an apocalyptic number.

665550066563 is a deficient number, since it is larger than the sum of its proper divisors (1).

665550066563 is an equidigital number, since it uses as much as digits as its factorization.

665550066563 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580000, while the sum is 53.

The spelling of 665550066563 in words is "six hundred sixty-five billion, five hundred fifty million, sixty-six thousand, five hundred sixty-three".