664631320770 has 96 divisors (see below), whose sum is σ = 1820399518080. Its totient is φ = 167776842240.

The previous prime is 664631320763. The next prime is 664631320807. The reversal of 664631320770 is 77023136466.

664631320770 is a `hidden beast` number, since 6 + 6 + 4 + 631 + 3 + 2 + 0 + 7 + 7 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2068035 + ... + 2367705.

It is an arithmetic number, because the mean of its divisors is an integer number (18962494980).

Almost surely, 2^664631320770 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664631320770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (910199759040).

664631320770 is an abundant number, since it is smaller than the sum of its proper divisors (1155768197310).

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

664631320770 is a wasteful number, since it uses less digits than its factorization.

664631320770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301000 (or 300997 counting only the distinct ones).

The product of its (nonzero) digits is 762048, while the sum is 45.

The spelling of 664631320770 in words is "six hundred sixty-four billion, six hundred thirty-one million, three hundred twenty thousand, seven hundred seventy".