664657785356 has 24 divisors (see below), whose sum is σ = 1177812342000. Its totient is φ = 328150082304.

The previous prime is 664657785347. The next prime is 664657785359. The reversal of 664657785356 is 653587756466.

It is a super-3 number, since 3×664657785356³ (a number of 36 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (68) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (664657785359) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1000121 + ... + 1526288.

It is an arithmetic number, because the mean of its divisors is an integer number (49075514250).

Almost surely, 2^664657785356 is an apocalyptic number.

It is an amenable number.

664657785356 is a deficient number, since it is larger than the sum of its proper divisors (513154556644).

664657785356 is a wasteful number, since it uses less digits than its factorization.

664657785356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2527241 (or 2527239 counting only the distinct ones).

The product of its digits is 762048000, while the sum is 68.

The spelling of 664657785356 in words is "six hundred sixty-four billion, six hundred fifty-seven million, seven hundred eighty-five thousand, three hundred fifty-six".