645140412 has 144 divisors (see below), whose sum is σ = 2022052032. Its totient is φ = 169205760.

The previous prime is 645140407. The next prime is 645140413. The reversal of 645140412 is 214041546.

645140412 is a `hidden beast` number, since 645 + 1 + 4 + 0 + 4 + 12 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645140413) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 173808 + ... + 177480.

It is an arithmetic number, because the mean of its divisors is an integer number (14042028).

Almost surely, 2^645140412 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 645140412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1011026016).

645140412 is an abundant number, since it is smaller than the sum of its proper divisors (1376911620).

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

645140412 is a wasteful number, since it uses less digits than its factorization.

645140412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3748 (or 3743 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 645140412 is about 25399.6144065220. The cubic root of 645140412 is about 864.0749517025.

Adding to 645140412 its reverse (214041546), we get a palindrome (859181958).

The spelling of 645140412 in words is "six hundred forty-five million, one hundred forty thousand, four hundred twelve".