640825470 has 48 divisors (see below), whose sum is σ = 1723606560. Its totient is φ = 164993472.

The previous prime is 640825469. The next prime is 640825477. The reversal of 640825470 is 74528046.

640825470 is a `hidden beast` number, since 640 + 8 + 2 + 5 + 4 + 7 + 0 = 666.

640825470 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640825477) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 120154 + ... + 125373.

It is an arithmetic number, because the mean of its divisors is an integer number (35908470).

Almost surely, 2^640825470 is an apocalyptic number.

640825470 is an abundant number, since it is smaller than the sum of its proper divisors (1082781090).

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

640825470 is a wasteful number, since it uses less digits than its factorization.

640825470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245569 (or 245566 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 640825470 is about 25314.5308074236. The cubic root of 640825470 is about 862.1442212524.

It can be divided in two parts, 6408 and 25470, that added together give a triangular number (31878 = T₂₅₂).

The spelling of 640825470 in words is "six hundred forty million, eight hundred twenty-five thousand, four hundred seventy".