645738912 has 384 divisors, whose sum is σ = 2384363520. Its totient is φ = 165473280.

The previous prime is 645738871. The next prime is 645738937. The reversal of 645738912 is 219837546.

645738912 is a `hidden beast` number, since 64 + 573 + 8 + 9 + 12 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3380737 + ... + 3380927.

It is an arithmetic number, because the mean of its divisors is an integer number (6209280).

Almost surely, 2^645738912 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 645738912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1192181760).

645738912 is an abundant number, since it is smaller than the sum of its proper divisors (1738624608).

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

645738912 is a wasteful number, since it uses less digits than its factorization.

645738912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273 (or 259 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 645738912 is about 25411.3933502278. The cubic root of 645738912 is about 864.3420713408.

It can be divided in two parts, 6457 and 38912, that added together give a square (45369 = 213²).

The spelling of 645738912 in words is "six hundred forty-five million, seven hundred thirty-eight thousand, nine hundred twelve".