668845056 has 88 divisors (see below), whose sum is σ = 1944879264. Its totient is φ = 202670080.

The previous prime is 668845039. The next prime is 668845061. The reversal of 668845056 is 650548866.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (88).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 668844996 and 668845014.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 23896 + ... + 43688.

Almost surely, 2^668845056 is an apocalyptic number.

668845056 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668845056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (972439632).

668845056 is an abundant number, since it is smaller than the sum of its proper divisors (1276034208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

668845056 is a wasteful number, since it uses less digits than its factorization.

668845056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19827 (or 19809 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 48.

The square root of 668845056 is about 25862.0388987411. The cubic root of 668845056 is about 874.5309294288.

The spelling of 668845056 in words is "six hundred sixty-eight million, eight hundred forty-five thousand, fifty-six".