645724296 has 192 divisors, whose sum is σ = 2120801280. Its totient is φ = 173560320.

The previous prime is 645724279. The next prime is 645724297. The reversal of 645724296 is 692427546.

645724296 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (645724297) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 577530 + ... + 578646.

It is an arithmetic number, because the mean of its divisors is an integer number (11045840).

Almost surely, 2^645724296 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 645724296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1060400640).

645724296 is an abundant number, since it is smaller than the sum of its proper divisors (1475076984).

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

645724296 is a wasteful number, since it uses less digits than its factorization.

645724296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1204 (or 1197 counting only the distinct ones).

The product of its digits is 725760, while the sum is 45.

The square root of 645724296 is about 25411.1057610644. The cubic root of 645724296 is about 864.3355499646.

The spelling of 645724296 in words is "six hundred forty-five million, seven hundred twenty-four thousand, two hundred ninety-six".