664578522566 has 32 divisors (see below), whose sum is σ = 1143748519680. Its totient is φ = 283702391136.

The previous prime is 664578522541. The next prime is 664578522589. The reversal of 664578522566 is 665225875466.

It is a happy number.

It is a super-2 number, since 2×664578522566² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 664578522499 and 664578522508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10574945 + ... + 10637603.

It is an arithmetic number, because the mean of its divisors is an integer number (35742141240).

Almost surely, 2^664578522566 is an apocalyptic number.

664578522566 is a deficient number, since it is larger than the sum of its proper divisors (479169997114).

664578522566 is a wasteful number, since it uses less digits than its factorization.

664578522566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65628.

The product of its digits is 145152000, while the sum is 62.

The spelling of 664578522566 in words is "six hundred sixty-four billion, five hundred seventy-eight million, five hundred twenty-two thousand, five hundred sixty-six".