640650132 has 72 divisors (see below), whose sum is σ = 1708980000. Its totient is φ = 201797568.

The previous prime is 640650097. The next prime is 640650137. The reversal of 640650132 is 231056046.

640650132 is a `hidden beast` number, since 6 + 4 + 0 + 650 + 1 + 3 + 2 = 666.

640650132 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 640650096 and 640650105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640650137) 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, 340378 + ... + 342254.

Almost surely, 2^640650132 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 640650132, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (854490000).

640650132 is an abundant number, since it is smaller than the sum of its proper divisors (1068329868).

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

640650132 is a wasteful number, since it uses less digits than its factorization.

640650132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2405 (or 2400 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 640650132 is about 25311.0673816811. The cubic root of 640650132 is about 862.0655828713.

The spelling of 640650132 in words is "six hundred forty million, six hundred fifty thousand, one hundred thirty-two".