664641251680 has 48 divisors (see below), whose sum is σ = 1794531382560. Its totient is φ = 227877000192.

The previous prime is 664641251663. The next prime is 664641251693. The reversal of 664641251680 is 86152146466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 296713725 + ... + 296715964.

It is an arithmetic number, because the mean of its divisors is an integer number (37386070470).

Almost surely, 2^664641251680 is an apocalyptic number.

It is an amenable number.

664641251680 is an abundant number, since it is smaller than the sum of its proper divisors (1129890130880).

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

664641251680 is a wasteful number, since it uses less digits than its factorization.

664641251680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593429711 (or 593429703 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 49.

The spelling of 664641251680 in words is "six hundred sixty-four billion, six hundred forty-one million, two hundred fifty-one thousand, six hundred eighty".