645200766 has 48 divisors (see below), whose sum is σ = 1604569824. Its totient is φ = 183543552.

The previous prime is 645200753. The next prime is 645200789. The reversal of 645200766 is 667002546.

645200766 is a `hidden beast` number, since 64 + 520 + 0 + 76 + 6 = 666.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 645200766.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18370 + ... + 40346.

It is an arithmetic number, because the mean of its divisors is an integer number (33428538).

Almost surely, 2^645200766 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645200766, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (802284912).

645200766 is an abundant number, since it is smaller than the sum of its proper divisors (959369058).

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

645200766 is a wasteful number, since it uses less digits than its factorization.

645200766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22225 (or 22222 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 645200766 is about 25400.8024676387. The cubic root of 645200766 is about 864.1018960971.

The spelling of 645200766 in words is "six hundred forty-five million, two hundred thousand, seven hundred sixty-six".