664845511850 has 48 divisors (see below), whose sum is σ = 1333073745528. Its totient is φ = 245234960640.

The previous prime is 664845511753. The next prime is 664845511853. The reversal of 664845511850 is 58115548466.

It can be written as a sum of positive squares in 12 ways, for example, as 55342092001 + 609503419849 = 235249^2 + 780707^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 664845511792 and 664845511801.

It is not an unprimeable number, because it can be changed into a prime (664845511853) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 135092 + ... + 1161008.

Almost surely, 2^664845511850 is an apocalyptic number.

664845511850 is an abundant number, since it is smaller than the sum of its proper divisors (668228233678).

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

664845511850 is a wasteful number, since it uses less digits than its factorization.

664845511850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026939 (or 1026934 counting only the distinct ones).

The product of its (nonzero) digits is 4608000, while the sum is 53.

The spelling of 664845511850 in words is "six hundred sixty-four billion, eight hundred forty-five million, five hundred eleven thousand, eight hundred fifty".