645294885984 has 768 divisors, whose sum is σ = 2367848448000. Its totient is φ = 166819461120.

The previous prime is 645294885967. The next prime is 645294886031. The reversal of 645294885984 is 489588492546.

645294885984 is a `hidden beast` number, since 6 + 4 + 5 + 29 + 4 + 8 + 8 + 598 + 4 = 666.

It is a super-3 number, since 3×645294885984³ (a number of 36 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (72) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 281418342 + ... + 281420634.

It is an arithmetic number, because the mean of its divisors is an integer number (3083136000).

Almost surely, 2^645294885984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645294885984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1183924224000).

645294885984 is an abundant number, since it is smaller than the sum of its proper divisors (1722553562016).

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

645294885984 is a wasteful number, since it uses less digits than its factorization.

645294885984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2448 (or 2434 counting only the distinct ones).

The product of its digits is 796262400, while the sum is 72.

The spelling of 645294885984 in words is "six hundred forty-five billion, two hundred ninety-four million, eight hundred eighty-five thousand, nine hundred eighty-four".