645290800 has 360 divisors, whose sum is σ = 2042962992. Its totient is φ = 193536000.

The previous prime is 645290797. The next prime is 645290819. The reversal of 645290800 is 8092546.

It is a happy number.

645290800 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 8839564 + ... + 8839636.

Almost surely, 2^645290800 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 645290800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1021481496).

645290800 is an abundant number, since it is smaller than the sum of its proper divisors (1397672192).

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

645290800 is a wasteful number, since it uses less digits than its factorization.

645290800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 645290800 is about 25402.5746726587. The cubic root of 645290800 is about 864.1420876859.

The spelling of 645290800 in words is "six hundred forty-five million, two hundred ninety thousand, eight hundred".