645574032 has 120 divisors (see below), whose sum is σ = 1846810368. Its totient is φ = 210470400.

The previous prime is 645574019. The next prime is 645574037. The reversal of 645574032 is 230475546.

645574032 is a `hidden beast` number, since 64 + 557 + 40 + 3 + 2 = 666.

645574032 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (645574037) 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, 2382057 + ... + 2382327.

Almost surely, 2^645574032 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 645574032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (923405184).

645574032 is an abundant number, since it is smaller than the sum of its proper divisors (1201236336).

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

645574032 is a wasteful number, since it uses less digits than its factorization.

645574032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 589 (or 580 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 36.

The square root of 645574032 is about 25408.1489290346. The cubic root of 645574032 is about 864.2684993706.

The spelling of 645574032 in words is "six hundred forty-five million, five hundred seventy-four thousand, thirty-two".