645203825 has 36 divisors (see below), whose sum is σ = 935838540. Its totient is φ = 439971840.

The previous prime is 645203807. The next prime is 645203831. The reversal of 645203825 is 528302546.

645203825 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 247009 + 644956816 = 497^2 + 25396^2 .

It is not a de Polignac number, because 645203825 - 2⁶ = 645203761 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 235061 + ... + 237789.

It is an arithmetic number, because the mean of its divisors is an integer number (25995515).

Almost surely, 2^645203825 is an apocalyptic number.

It is an amenable number.

645203825 is a deficient number, since it is larger than the sum of its proper divisors (290634715).

645203825 is a wasteful number, since it uses less digits than its factorization.

645203825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2946 (or 2934 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

The square root of 645203825 is about 25400.8626822004. The cubic root of 645203825 is about 864.1032617100.

The spelling of 645203825 in words is "six hundred forty-five million, two hundred three thousand, eight hundred twenty-five".